CWE-78
AllowedImproper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Abstraction: Base · Status: Stable
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.
8343 vulnerabilities reference this CWE, most recent first.
GHSA-JQ63-3P3V-M99F
Vulnerability from github – Published: 2022-05-24 16:58 – Updated: 2024-04-04 02:09MyBuilder viewer before 6.2.2019.814 allow an attacker to execute arbitrary command via specifically crafted configuration file. This can be leveraged for code execution.
{
"affected": [],
"aliases": [
"CVE-2019-12812"
],
"database_specific": {
"cwe_ids": [
"CWE-78"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2019-10-07T15:15:00Z",
"severity": "CRITICAL"
},
"details": "MyBuilder viewer before 6.2.2019.814 allow an attacker to execute arbitrary command via specifically crafted configuration file. This can be leveraged for code execution.",
"id": "GHSA-jq63-3p3v-m99f",
"modified": "2024-04-04T02:09:46Z",
"published": "2022-05-24T16:58:00Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-12812"
},
{
"type": "WEB",
"url": "https://www.boho.or.kr/krcert/secNoticeView.do?bulletin_writing_sequence=35155"
}
],
"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"
}
]
}
GHSA-JQ84-6FMM-6QV6
Vulnerability from github – Published: 2022-05-24 17:28 – Updated: 2022-12-29 01:42Perfecto Plugin allows specifying Perfecto Connect Path and Perfecto Connect File Name in job configurations.
This command is executed on the Jenkins controller in Perfecto Plugin 1.17 and earlier, allowing attackers with Job/Configure permission to run arbitrary commands on the Jenkins controller.
Perfecto Plugin 1.18 executes the specified commands on the agent the build is running on.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 1.17"
},
"package": {
"ecosystem": "Maven",
"name": "io.jenkins.plugins:perfecto"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.18"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2020-2261"
],
"database_specific": {
"cwe_ids": [
"CWE-78"
],
"github_reviewed": true,
"github_reviewed_at": "2022-12-29T01:42:56Z",
"nvd_published_at": "2020-09-16T14:15:00Z",
"severity": "HIGH"
},
"details": "Perfecto Plugin allows specifying Perfecto Connect Path and Perfecto Connect File Name in job configurations.\n\nThis command is executed on the Jenkins controller in Perfecto Plugin 1.17 and earlier, allowing attackers with Job/Configure permission to run arbitrary commands on the Jenkins controller.\n\nPerfecto Plugin 1.18 executes the specified commands on the agent the build is running on.",
"id": "GHSA-jq84-6fmm-6qv6",
"modified": "2022-12-29T01:42:56Z",
"published": "2022-05-24T17:28:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-2261"
},
{
"type": "PACKAGE",
"url": "https://github.com/jenkinsci/perfecto-plugin"
},
{
"type": "WEB",
"url": "https://www.jenkins.io/security/advisory/2020-09-16/#SECURITY-1980"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2020/09/16/3"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "OS command execution vulnerability in Perfecto Plugin"
}
GHSA-JQ8R-C5MQ-7JCX
Vulnerability from github – Published: 2022-05-13 01:50 – Updated: 2022-05-13 01:50On D-Link DIR-823G devices, the GoAhead configuration allows /HNAP1 Command Injection via shell metacharacters in the POST data, because this data is sent directly to the "system" library function.
{
"affected": [],
"aliases": [
"CVE-2018-17787"
],
"database_specific": {
"cwe_ids": [
"CWE-78"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2018-10-02T18:29:00Z",
"severity": "CRITICAL"
},
"details": "On D-Link DIR-823G devices, the GoAhead configuration allows /HNAP1 Command Injection via shell metacharacters in the POST data, because this data is sent directly to the \"system\" library function.",
"id": "GHSA-jq8r-c5mq-7jcx",
"modified": "2022-05-13T01:50:34Z",
"published": "2022-05-13T01:50:34Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2018-17787"
},
{
"type": "WEB",
"url": "https://xz.aliyun.com/t/2834"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-JQC2-W244-P56P
Vulnerability from github – Published: 2026-06-23 15:32 – Updated: 2026-06-23 15:32NetComm NF20MESH routers running firmware R6B031 and earlier contain an authenticated remote code execution vulnerability that allows authenticated attackers to execute arbitrary commands as root by injecting shell metacharacters into the username JSON parameter processed by the dalStorage_addUserAccount function. Attackers can exploit the unsafe concatenation of user-supplied input into a shell command string passed to rut_doSystemAction without sanitization to achieve full root-level command execution on the underlying operating system.
{
"affected": [],
"aliases": [
"CVE-2026-35018"
],
"database_specific": {
"cwe_ids": [
"CWE-78"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-23T15:16:33Z",
"severity": "HIGH"
},
"details": "NetComm NF20MESH routers running firmware R6B031 and earlier contain an authenticated remote code execution vulnerability that allows authenticated attackers to execute arbitrary commands as root by injecting shell metacharacters into the username JSON parameter processed by the dalStorage_addUserAccount function. Attackers can exploit the unsafe concatenation of user-supplied input into a shell command string passed to rut_doSystemAction without sanitization to achieve full root-level command execution on the underlying operating system.",
"id": "GHSA-jqc2-w244-p56p",
"modified": "2026-06-23T15:32:37Z",
"published": "2026-06-23T15:32:37Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-35018"
},
{
"type": "WEB",
"url": "https://signal11.io/advisories/netcomm-nf20-mesh-remote-code-execution"
},
{
"type": "WEB",
"url": "https://support.netcommwireless.com/api/Media/Firmware/4407c21d-e990-49a4-9754-b72475f20c76?Product=NF20MESH%20Release%20Notes.pdf"
},
{
"type": "WEB",
"url": "https://support.netcommwireless.com/products/nf20mesh#Firmware"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/netcomm-nf20mesh-r6b032-authenticated-rce-via-os-command-injection"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/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-JQCF-6MG8-WXX4
Vulnerability from github – Published: 2026-02-03 06:31 – Updated: 2026-02-06 21:30A vulnerability in Brocade Fabric OS could allow an authenticated, local attacker with privileges to access the Bash shell to access insecurely stored file contents including the history command.
{
"affected": [],
"aliases": [
"CVE-2026-0383"
],
"database_specific": {
"cwe_ids": [
"CWE-78"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-02-03T04:15:55Z",
"severity": "HIGH"
},
"details": "A vulnerability in Brocade Fabric OS could allow an authenticated, local attacker with privileges to access the Bash shell to access insecurely stored file contents including the history command.",
"id": "GHSA-jqcf-6mg8-wxx4",
"modified": "2026-02-06T21:30:48Z",
"published": "2026-02-03T06:31:04Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-0383"
},
{
"type": "WEB",
"url": "https://support.broadcom.com/web/ecx/support-content-notification/-/external/content/SecurityAdvisories/0/36851"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/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-JQHG-J5GV-HPMR
Vulnerability from github – Published: 2026-02-23 21:31 – Updated: 2026-02-25 15:31TOTOLINK X6000R v9.4.0cu.1498_B20250826 contains an OS command injection vulnerability in the NTPSyncWithHost handler of the /usr/sbin/shttpd executable. The host_time parameter is retrieved via sub_40C404 and passed to a date -s shell command through CsteSystem. While the first two tokens of the input are validated, the remainder of the string is not sanitized, allowing authenticated attackers to execute arbitrary shell commands via shell metacharacters.
{
"affected": [],
"aliases": [
"CVE-2025-70328"
],
"database_specific": {
"cwe_ids": [
"CWE-78",
"CWE-94"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-02-23T21:19:09Z",
"severity": "HIGH"
},
"details": "TOTOLINK X6000R v9.4.0cu.1498_B20250826 contains an OS command injection vulnerability in the NTPSyncWithHost handler of the /usr/sbin/shttpd executable. The host_time parameter is retrieved via sub_40C404 and passed to a date -s shell command through CsteSystem. While the first two tokens of the input are validated, the remainder of the string is not sanitized, allowing authenticated attackers to execute arbitrary shell commands via shell metacharacters.",
"id": "GHSA-jqhg-j5gv-hpmr",
"modified": "2026-02-25T15:31:37Z",
"published": "2026-02-23T21:31:27Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-70328"
},
{
"type": "WEB",
"url": "https://github.com/neighborhood-H/0-DAY/blob/main/Toto-link/X6000R/NTPSyncWihtHost/report.md"
},
{
"type": "WEB",
"url": "https://www.notion.so/TOTOLINK-X6000R-NTPSyncWithHost-2d170566ca7f803a8096c1b31b2ed42f?source=copy_link"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-JQP5-9296-XF42
Vulnerability from github – Published: 2026-05-28 21:32 – Updated: 2026-05-28 21:32Exposed methods allow authenticated users to create and execute arbitrary JavaScript code on the server. The scripts execute with full access, enabling complete system compromise as commands are executed as root.
{
"affected": [],
"aliases": [
"CVE-2026-9645"
],
"database_specific": {
"cwe_ids": [
"CWE-78"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-05-28T21:16:34Z",
"severity": "CRITICAL"
},
"details": "Exposed methods allow authenticated users to create and execute arbitrary JavaScript code on the server. The scripts execute with full access, enabling complete system compromise as commands are executed as root.",
"id": "GHSA-jqp5-9296-xf42",
"modified": "2026-05-28T21:32:07Z",
"published": "2026-05-28T21:32:07Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-9645"
},
{
"type": "WEB",
"url": "https://www.tenable.com/security/research/tra-2026-46"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-JQPQ-MGVM-F9R6
Vulnerability from github – Published: 2026-02-18 00:55 – Updated: 2026-03-06 01:04Command hijacking via PATH handling
Discovered: 2026-02-04 Reporter: @akhmittra
Summary
OpenClaw previously accepted untrusted PATH sources in limited situations. In affected versions, this could cause OpenClaw to resolve and execute an unintended binary ("command hijacking") when running host commands.
This issue primarily matters when OpenClaw is relying on allowlist/safe-bin protections and expects PATH to be trustworthy.
Affected Packages / Versions
- Package:
openclaw(npm) - Affected:
< 2026.2.14 - Patched:
>= 2026.2.14(planned next release)
What Is Required To Trigger This
A) Node Host PATH override (remote command hijack)
An attacker needs all of the following:
- Authenticated/authorized access to an execution surface that can invoke node-host execution (for example, a compromised gateway or a caller that can issue
system.run). - A node host connected and exposing
system.run. - A configuration where allowlist/safe-bins are expected to restrict execution (this is not meaningful if full arbitrary exec is already allowed).
- The ability to pass request-scoped environment overrides (specifically
PATH) intosystem.run. - A way to place an attacker-controlled executable earlier in
PATH(for example, a writable directory on the node host), with a name that matches an allowlisted/safe-bin command that OpenClaw will run.
Notes:
- OpenClaw deployments commonly require a gateway token/password (or equivalent transport authentication). This should not be treated as unauthenticated Internet RCE.
- This scenario typically depends on non-standard / misconfigured deployments (for example, granting untrusted parties access to invoke node-host execution or otherwise exposing a privileged execution surface beyond the intended trust boundary).
B) Project-local PATH bootstrapping (local command hijack)
An attacker needs all of the following:
- The victim runs OpenClaw from within an attacker-controlled working directory (for example, cloning and running inside a malicious repository).
- That directory contains a
node_modules/.bin/openclawand additional attacker-controlled executables in the same directory. - OpenClaw subsequently executes a command by name (resolved via
PATH) that matches one of those attacker-controlled executables.
Fix
- Project-local
node_modules/.binPATH bootstrapping is now disabled by default. If explicitly enabled, it is append-only (never prepended) viaOPENCLAW_ALLOW_PROJECT_LOCAL_BIN=1. - Node Host now ignores request-scoped
PATHoverrides.
Fix Commit(s)
- 013e8f6b3be3333a229a066eef26a45fec47ffcc
Thanks @akhmittra for reporting.
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "openclaw"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2026.2.14"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-29610"
],
"database_specific": {
"cwe_ids": [
"CWE-427",
"CWE-78",
"CWE-807"
],
"github_reviewed": true,
"github_reviewed_at": "2026-02-18T00:55:50Z",
"nvd_published_at": "2026-03-05T22:16:24Z",
"severity": "HIGH"
},
"details": "# Command hijacking via PATH handling\n\n**Discovered:** 2026-02-04\n**Reporter:** @akhmittra\n\n## Summary\n\nOpenClaw previously accepted untrusted PATH sources in limited situations. In affected versions, this could cause OpenClaw to resolve and execute an unintended binary (\"command hijacking\") when running host commands.\n\nThis issue primarily matters when OpenClaw is relying on allowlist/safe-bin protections and expects `PATH` to be trustworthy.\n\n## Affected Packages / Versions\n\n- Package: `openclaw` (npm)\n- Affected: `\u003c 2026.2.14`\n- Patched: `\u003e= 2026.2.14` (planned next release)\n\n## What Is Required To Trigger This\n\n### A) Node Host PATH override (remote command hijack)\n\nAn attacker needs all of the following:\n\n- Authenticated/authorized access to an execution surface that can invoke node-host execution (for example, a compromised gateway or a caller that can issue `system.run`).\n- A node host connected and exposing `system.run`.\n- A configuration where allowlist/safe-bins are expected to restrict execution (this is not meaningful if full arbitrary exec is already allowed).\n- The ability to pass request-scoped environment overrides (specifically `PATH`) into `system.run`.\n- A way to place an attacker-controlled executable earlier in `PATH` (for example, a writable directory on the node host), with a name that matches an allowlisted/safe-bin command that OpenClaw will run.\n\nNotes:\n\n- OpenClaw deployments commonly require a gateway token/password (or equivalent transport authentication). This should not be treated as unauthenticated Internet RCE.\n- This scenario typically depends on **non-standard / misconfigured deployments** (for example, granting untrusted parties access to invoke node-host execution or otherwise exposing a privileged execution surface beyond the intended trust boundary).\n\n### B) Project-local PATH bootstrapping (local command hijack)\n\nAn attacker needs all of the following:\n\n- The victim runs OpenClaw from within an attacker-controlled working directory (for example, cloning and running inside a malicious repository).\n- That directory contains a `node_modules/.bin/openclaw` and additional attacker-controlled executables in the same directory.\n- OpenClaw subsequently executes a command by name (resolved via `PATH`) that matches one of those attacker-controlled executables.\n\n## Fix\n\n- Project-local `node_modules/.bin` PATH bootstrapping is now **disabled by default**. If explicitly enabled, it is **append-only** (never prepended) via `OPENCLAW_ALLOW_PROJECT_LOCAL_BIN=1`.\n- Node Host now ignores request-scoped `PATH` overrides.\n\n## Fix Commit(s)\n\n- 013e8f6b3be3333a229a066eef26a45fec47ffcc\n\nThanks @akhmittra for reporting.",
"id": "GHSA-jqpq-mgvm-f9r6",
"modified": "2026-03-06T01:04:18Z",
"published": "2026-02-18T00:55:50Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-jqpq-mgvm-f9r6"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-29610"
},
{
"type": "WEB",
"url": "https://github.com/openclaw/openclaw/commit/013e8f6b3be3333a229a066eef26a45fec47ffcc"
},
{
"type": "PACKAGE",
"url": "https://github.com/openclaw/openclaw"
},
{
"type": "WEB",
"url": "https://github.com/openclaw/openclaw/releases/tag/v2026.2.14"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/openclaw-command-hijacking-via-unsafe-path-handling"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "OpenClaw: Command hijacking via unsafe PATH handling (bootstrapping + node-host PATH overrides)"
}
GHSA-JQQ3-XMGH-4V27
Vulnerability from github – Published: 2022-05-17 04:10 – Updated: 2022-05-17 04:10Webservice-DIC yoyaku_v41 allows remote attackers to execute arbitrary OS commands via unspecified vectors.
{
"affected": [],
"aliases": [
"CVE-2015-2979"
],
"database_specific": {
"cwe_ids": [
"CWE-78"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2015-07-29T14:59:00Z",
"severity": "HIGH"
},
"details": "Webservice-DIC yoyaku_v41 allows remote attackers to execute arbitrary OS commands via unspecified vectors.",
"id": "GHSA-jqq3-xmgh-4v27",
"modified": "2022-05-17T04:10:41Z",
"published": "2022-05-17T04:10:41Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2015-2979"
},
{
"type": "WEB",
"url": "http://jvn.jp/en/jp/JVN17522792/index.html"
},
{
"type": "WEB",
"url": "http://jvndb.jvn.jp/jvndb/JVNDB-2015-000109"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-JQQM-2P4M-968Q
Vulnerability from github – Published: 2025-06-10 09:30 – Updated: 2025-06-10 09:30CWE-78: I Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') vulnerability exists that could cause remote control over the charging station when an authenticated user modifies configuration parameters on the web server.
{
"affected": [],
"aliases": [
"CVE-2025-5743"
],
"database_specific": {
"cwe_ids": [
"CWE-78"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-06-10T09:15:25Z",
"severity": "HIGH"
},
"details": "CWE-78: I Improper Neutralization of Special Elements used in an OS Command (\u0027OS Command Injection\u0027)\nvulnerability exists that could cause remote control over the charging station when an authenticated user\nmodifies configuration parameters on the web server.",
"id": "GHSA-jqqm-2p4m-968q",
"modified": "2025-06-10T09:30:31Z",
"published": "2025-06-10T09:30:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-5743"
},
{
"type": "WEB",
"url": "https://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2025-161-03\u0026p_enDocType=Security+and+Safety+Notice\u0026p_File_Name=SEVD-2025-161-03.pdf"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:H/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:H/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"
}
]
}
Mitigation
If at all possible, use library calls rather than external processes to recreate the desired functionality.
Mitigation MIT-22
Strategy: Sandbox or Jail
- Run the code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
- OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
- This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
- Be careful to avoid CWE-243 and other weaknesses related to jails.
Mitigation
Strategy: Attack Surface Reduction
For any data that will be used to generate a command to be executed, keep as much of that data out of external control as possible. For example, in web applications, this may require storing the data locally in the session's state instead of sending it out to the client in a hidden form field.
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 MIT-4.3
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 the ESAPI Encoding control [REF-45] or a similar tool, library, or framework. These will help the programmer encode outputs in a manner less prone to error.
Mitigation MIT-28
Strategy: Output Encoding
While it is risky to use dynamically-generated query strings, code, or commands that mix control and data together, sometimes it may be unavoidable. Properly quote arguments and escape any special characters within those arguments. The most conservative approach is to escape or filter all characters that do not pass an extremely strict allowlist (such as everything that is not alphanumeric or white space). If some special characters are still needed, such as white space, wrap each argument in quotes after the escaping/filtering step. Be careful of argument injection (CWE-88).
Mitigation
If the program to be executed allows arguments to be specified within an input file or from standard input, then consider using that mode to pass arguments instead of the command line.
Mitigation MIT-27
Strategy: Parameterization
- If available, use structured mechanisms that automatically enforce the separation between data and code. These mechanisms may be able to provide the relevant quoting, encoding, and validation automatically, instead of relying on the developer to provide this capability at every point where output is generated.
- Some languages offer multiple functions that can be used to invoke commands. Where possible, identify any function that invokes a command shell using a single string, and replace it with a function that requires individual arguments. These functions typically perform appropriate quoting and filtering of arguments. For example, in C, the system() function accepts a string that contains the entire command to be executed, whereas execl(), execve(), and others require an array of strings, one for each argument. In Windows, CreateProcess() only accepts one command at a time. In Perl, if system() is provided with an array of arguments, then it will quote each of the arguments.
Mitigation MIT-5
Strategy: Input Validation
- Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
- When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
- When constructing OS command strings, use stringent allowlists that limit the character set based on the expected value of the parameter in the request. This will indirectly limit the scope of an attack, but this technique is less important than proper output encoding and escaping.
- Note that proper output encoding, escaping, and quoting is the most effective solution for preventing OS command injection, although input validation may provide some defense-in-depth. This is because it effectively limits what will appear in output. Input validation will not always prevent OS command injection, especially if you are required to support free-form text fields that could contain arbitrary characters. For example, when invoking a mail program, you might need to allow the subject field to contain otherwise-dangerous inputs like ";" and ">" characters, which would need to be escaped or otherwise handled. In this case, stripping the character might reduce the risk of OS command injection, but it would produce incorrect behavior because the subject field would not be recorded as the user intended. This might seem to be a minor inconvenience, but it could be more important when the program relies on well-structured subject lines in order to pass messages to other components.
- Even if you make a mistake in your validation (such as forgetting one out of 100 input fields), appropriate encoding is still likely to protect you from injection-based attacks. As long as it is not done in isolation, input validation is still a useful technique, since it may significantly reduce your attack surface, allow you to detect some attacks, and provide other security benefits that proper encoding does not address.
Mitigation MIT-21
Strategy: Enforcement by Conversion
When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
Mitigation MIT-32
Strategy: Compilation or Build Hardening
Run the code in an environment that performs automatic taint propagation and prevents any command execution that uses tainted variables, such as Perl's "-T" switch. This will force the program to perform validation steps that remove the taint, although you must be careful to correctly validate your inputs so that you do not accidentally mark dangerous inputs as untainted (see CWE-183 and CWE-184).
Mitigation MIT-32
Strategy: Environment Hardening
Run the code in an environment that performs automatic taint propagation and prevents any command execution that uses tainted variables, such as Perl's "-T" switch. This will force the program to perform validation steps that remove the taint, although you must be careful to correctly validate your inputs so that you do not accidentally mark dangerous inputs as untainted (see CWE-183 and CWE-184).
Mitigation MIT-39
- Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success.
- If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages can be viewed by attackers. Highly sensitive information such as passwords should never be saved to log files.
- Avoid inconsistent messaging that might accidentally tip off an attacker about internal state, such as whether a user account exists or not.
- In the context of OS Command Injection, error information passed back to the user might reveal whether an OS command is being executed and possibly which command is being used.
Mitigation
Strategy: Sandbox or Jail
Use runtime policy enforcement to create an allowlist of allowable commands, then prevent use of any command that does not appear in the allowlist. Technologies such as AppArmor are available to do this.
Mitigation MIT-29
Strategy: Firewall
Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth [REF-1481].
Mitigation MIT-17
Strategy: Environment Hardening
Run your code using the lowest privileges that are required to accomplish the necessary tasks [REF-76]. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.
Mitigation MIT-16
Strategy: Environment Hardening
When using PHP, configure the application so that it does not use register_globals. During implementation, develop the application so that it does not rely on this feature, but be wary of implementing a register_globals emulation that is subject to weaknesses such as CWE-95, CWE-621, and similar issues.
CAPEC-108: Command Line Execution through SQL Injection
An attacker uses standard SQL injection methods to inject data into the command line for execution. This could be done directly through misuse of directives such as MSSQL_xp_cmdshell or indirectly through injection of data into the database that would be interpreted as shell commands. Sometime later, an unscrupulous backend application (or could be part of the functionality of the same application) fetches the injected data stored in the database and uses this data as command line arguments without performing proper validation. The malicious data escapes that data plane by spawning new commands to be executed on the host.
CAPEC-15: Command Delimiters
An attack of this type exploits a programs' vulnerabilities that allows an attacker's commands to be concatenated onto a legitimate command with the intent of targeting other resources such as the file system or database. The system that uses a filter or denylist input validation, as opposed to allowlist validation is vulnerable to an attacker who predicts delimiters (or combinations of delimiters) not present in the filter or denylist. As with other injection attacks, the attacker uses the command delimiter payload as an entry point to tunnel through the application and activate additional attacks through SQL queries, shell commands, network scanning, and so on.
CAPEC-43: Exploiting Multiple Input Interpretation Layers
An attacker supplies the target software with input data that contains sequences of special characters designed to bypass input validation logic. This exploit relies on the target making multiples passes over the input data and processing a "layer" of special characters with each pass. In this manner, the attacker can disguise input that would otherwise be rejected as invalid by concealing it with layers of special/escape characters that are stripped off by subsequent processing steps. The goal is to first discover cases where the input validation layer executes before one or more parsing layers. That is, user input may go through the following logic in an application: <parser1> --> <input validator> --> <parser2>. In such cases, the attacker will need to provide input that will pass through the input validator, but after passing through parser2, will be converted into something that the input validator was supposed to stop.
CAPEC-6: Argument Injection
An attacker changes the behavior or state of a targeted application through injecting data or command syntax through the targets use of non-validated and non-filtered arguments of exposed services or methods.
CAPEC-88: OS Command Injection
In this type of an attack, an adversary injects operating system commands into existing application functions. An application that uses untrusted input to build command strings is vulnerable. An adversary can leverage OS command injection in an application to elevate privileges, execute arbitrary commands and compromise the underlying operating system.