CWE-662
DiscouragedImproper Synchronization
Abstraction: Class · Status: Draft
The product utilizes multiple threads, processes, components, or systems to allow temporary access to a shared resource that can only be exclusive to one process at a time, but it does not properly synchronize these actions, which might cause simultaneous accesses of this resource by multiple threads or processes.
72 vulnerabilities reference this CWE, most recent first.
GHSA-3HJ2-HH36-HV9V
Vulnerability from github – Published: 2021-08-25 20:51 – Updated: 2023-06-13 22:11In the affected versions of this crate, Demuxer unconditionally implemented Send with no trait bounds on T. This allows sending a non-Send type T across thread boundaries, which can cause undefined behavior like unlocking a mutex from a thread that didn't lock the mutex, or memory corruption from data race. The flaw was corrected in commit 0562cbf by adding a T: Send bound to the Send impl for Demuxer.
{
"affected": [
{
"package": {
"ecosystem": "crates.io",
"name": "va-ts"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.0.4"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2020-36220"
],
"database_specific": {
"cwe_ids": [
"CWE-662",
"CWE-667",
"CWE-787"
],
"github_reviewed": true,
"github_reviewed_at": "2021-08-19T18:47:06Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"details": "In the affected versions of this crate, Demuxer\u003cT\u003e unconditionally implemented Send with no trait bounds on T. This allows sending a non-Send type T across thread boundaries, which can cause undefined behavior like unlocking a mutex from a thread that didn\u0027t lock the mutex, or memory corruption from data race. The flaw was corrected in commit `0562cbf` by adding a T: Send bound to the Send impl for Demuxer\u003cT\u003e.",
"id": "GHSA-3hj2-hh36-hv9v",
"modified": "2023-06-13T22:11:43Z",
"published": "2021-08-25T20:51:56Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-36220"
},
{
"type": "WEB",
"url": "https://github.com/video-audio/va-ts/issues/4"
},
{
"type": "PACKAGE",
"url": "https://github.com/video-audio/va-ts"
},
{
"type": "WEB",
"url": "https://rustsec.org/advisories/RUSTSEC-2020-0114.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
],
"summary": "Data race in va-ts"
}
GHSA-3JC5-5HC5-33GJ
Vulnerability from github – Published: 2021-08-25 20:50 – Updated: 2023-06-13 17:00Affected versions of conquer-once implements Sync for its OnceCell type without restricting it to Sendable types.
This allows non-Send but Sync types such as MutexGuard to be sent across threads leading to undefined behavior and memory corruption in concurrent programs.
The issue was fixed by adding a Send constraint to OnceCell.
{
"affected": [
{
"package": {
"ecosystem": "crates.io",
"name": "conquer-once"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.3.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2020-36208"
],
"database_specific": {
"cwe_ids": [
"CWE-662",
"CWE-787"
],
"github_reviewed": true,
"github_reviewed_at": "2021-08-19T18:51:18Z",
"nvd_published_at": null,
"severity": "HIGH"
},
"details": "Affected versions of conquer-once implements Sync for its OnceCell type without restricting it to Sendable types.\n\nThis allows non-Send but Sync types such as MutexGuard to be sent across threads leading to undefined behavior and memory corruption in concurrent programs.\n\nThe issue was fixed by adding a Send constraint to OnceCell.",
"id": "GHSA-3jc5-5hc5-33gj",
"modified": "2023-06-13T17:00:10Z",
"published": "2021-08-25T20:50:49Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-36208"
},
{
"type": "WEB",
"url": "https://github.com/oliver-giersch/conquer-once/issues/3"
},
{
"type": "PACKAGE",
"url": "https://github.com/oliver-giersch/conquer-once"
},
{
"type": "WEB",
"url": "https://rustsec.org/advisories/RUSTSEC-2020-0101.html"
}
],
"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"
}
],
"summary": "Data races in conquer-once"
}
GHSA-3JP7-754V-MG2Q
Vulnerability from github – Published: 2023-02-06 21:30 – Updated: 2023-02-14 03:30In ccd, there is a possible memory corruption due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS07326547; Issue ID: ALPS07326547.
{
"affected": [],
"aliases": [
"CVE-2022-32642"
],
"database_specific": {
"cwe_ids": [
"CWE-662"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-02-06T20:15:00Z",
"severity": "MODERATE"
},
"details": "In ccd, there is a possible memory corruption due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS07326547; Issue ID: ALPS07326547.",
"id": "GHSA-3jp7-754v-mg2q",
"modified": "2023-02-14T03:30:21Z",
"published": "2023-02-06T21:30:30Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-32642"
},
{
"type": "WEB",
"url": "https://corp.mediatek.com/product-security-bulletin/February-2023"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-45M3-398W-M2M9
Vulnerability from github – Published: 2026-03-02 21:41 – Updated: 2026-03-05 22:49Summary
An unauthenticated denial-of-service vulnerability exists in OliveTin’s OAuth2 login flow. Concurrent requests to /oauth/login can trigger unsynchronized access to a shared registeredStates map, causing a Go runtime panic (fatal error: concurrent map writes) and process termination. This allows remote attackers to crash the service when OAuth2 is enabled.
Details
The OAuth2 handler stores per-login state in a shared map without synchronization:
- service/internal/auth/otoauth2/restapi_auth_oauth2.go:24 registeredStates map[string]*oauth2State
- Unlocked write in login handler: .../restapi_auth_oauth2.go:141
- Unlocked read in callback check: .../restapi_auth_oauth2.go:174
- Unlocked writes in callback flow: .../restapi_auth_oauth2.go:284-285
- Unlocked read in auth chain check: .../restapi_auth_oauth2.go:376
These paths are network reachable via publicly registered routes:
- service/internal/httpservers/frontend.go:71 → /oauth/login
- service/internal/httpservers/frontend.go:72 → /oauth/callback
Because Go HTTP handlers run concurrently, high parallel traffic to /oauth/login causes concurrent map access and runtime panic.
Tested on:
- Container image: ghcr.io/olivetin/olivetin:3000.10.0
- Source also contains same pattern at commit/tag eb42029b5d0c0633551621288180dd4566b913f7 (3000.10.1)
PoC
- Start OliveTin with OAuth2 provider configured (example github), exposing port 1337.
- Confirm baseline:
curl -i http://127.0.0.1:1337/readyz
curl -i "http://127.0.0.1:1337/oauth/login?provider=github"
Expected: 200 for /readyz, 302 for /oauth/login.
- Run concurrency PoC:
python3 /OliveTin/tools/poc_oauth2_state_map_race_dos.py \
--base-url http://127.0.0.1:1337 \
--provider github \
--workers 80 \
--requests 120000 \
--health-failures 3
- Verify crash:
docker inspect olivetin-dos --format 'status={{.State.Status}} exit={{.State.ExitCode}}' docker logs olivetin-dos 2>&1 | grep -E "fatal error: concurrent map|concurrent map writes|restapi_auth_oauth2.go"
Observed result:
- Process exited with code 2
- Logs include:
- fatal error: concurrent map writes
- .../internal/auth/otoauth2/restapi_auth_oauth2.go:141 in HandleOAuthLogin
Impact
- Vulnerability type: Race condition (CWE-362) leading to DoS.
- Attacker requirements: network access only; no authentication required for exploit path.
- Impacted deployments: OliveTin instances with OAuth2 enabled and reachable over network.
- Security impact: remote unauthenticated attacker can repeatedly crash OliveTin, causing availability loss until restart/recovery.
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/OliveTin/OliveTin"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.0.0-20260301235225-f044d90d5525c"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-28789"
],
"database_specific": {
"cwe_ids": [
"CWE-362",
"CWE-400",
"CWE-662"
],
"github_reviewed": true,
"github_reviewed_at": "2026-03-02T21:41:36Z",
"nvd_published_at": "2026-03-05T20:16:16Z",
"severity": "HIGH"
},
"details": "### Summary\nAn unauthenticated denial-of-service vulnerability exists in OliveTin\u2019s OAuth2 login flow. Concurrent requests to /oauth/login can trigger unsynchronized access to a shared registeredStates map, causing a Go runtime panic (fatal\n error: concurrent map writes) and process termination. This allows remote attackers to crash the service when OAuth2 is enabled.\n\n\n### Details\nThe OAuth2 handler stores per-login state in a shared map without synchronization:\n\n - service/internal/auth/otoauth2/restapi_auth_oauth2.go:24\n registeredStates map[string]*oauth2State\n - Unlocked write in login handler: .../restapi_auth_oauth2.go:141\n - Unlocked read in callback check: .../restapi_auth_oauth2.go:174\n - Unlocked writes in callback flow: .../restapi_auth_oauth2.go:284-285\n - Unlocked read in auth chain check: .../restapi_auth_oauth2.go:376\n\n These paths are network reachable via publicly registered routes:\n```bash\n - service/internal/httpservers/frontend.go:71 \u2192 /oauth/login\n - service/internal/httpservers/frontend.go:72 \u2192 /oauth/callback\n```\n Because Go HTTP handlers run concurrently, high parallel traffic to /oauth/login causes concurrent map access and runtime panic.\n\n Tested on:\n\n - Container image: ghcr.io/olivetin/olivetin:3000.10.0\n - Source also contains same pattern at commit/tag eb42029b5d0c0633551621288180dd4566b913f7 (3000.10.1)\n\n\n### PoC\n1. Start OliveTin with OAuth2 provider configured (example github), exposing port 1337.\n 2. Confirm baseline:\n```bash\n curl -i http://127.0.0.1:1337/readyz\n curl -i \"http://127.0.0.1:1337/oauth/login?provider=github\"\n```\n Expected: 200 for /readyz, 302 for /oauth/login.\n\n 3. Run concurrency PoC:\n```bash\n python3 /OliveTin/tools/poc_oauth2_state_map_race_dos.py \\\n --base-url http://127.0.0.1:1337 \\\n --provider github \\\n --workers 80 \\\n --requests 120000 \\\n --health-failures 3\n```\n 4. Verify crash:\n\n docker inspect olivetin-dos --format \u0027status={{.State.Status}} exit={{.State.ExitCode}}\u0027\n docker logs olivetin-dos 2\u003e\u00261 | grep -E \"fatal error: concurrent map|concurrent map writes|restapi_auth_oauth2.go\"\n\n Observed result:\n\n - Process exited with code 2\n - Logs include:\n - fatal error: concurrent map writes\n - .../internal/auth/otoauth2/restapi_auth_oauth2.go:141 in HandleOAuthLogin\n\n\n\n### Impact\n- Vulnerability type: Race condition (CWE-362) leading to DoS.\n - Attacker requirements: network access only; no authentication required for exploit path.\n - Impacted deployments: OliveTin instances with OAuth2 enabled and reachable over network.\n - Security impact: remote unauthenticated attacker can repeatedly crash OliveTin, causing availability loss until restart/recovery.\n \n[poc_oauth2_state_map_race_dos.py](https://github.com/user-attachments/files/25577901/poc_oauth2_state_map_race_dos.py)",
"id": "GHSA-45m3-398w-m2m9",
"modified": "2026-03-05T22:49:34Z",
"published": "2026-03-02T21:41:36Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/OliveTin/OliveTin/security/advisories/GHSA-45m3-398w-m2m9"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-28789"
},
{
"type": "WEB",
"url": "https://github.com/OliveTin/OliveTin/commit/f044d90d5525c4c8e3f421b32ed7eff771c22d36"
},
{
"type": "PACKAGE",
"url": "https://github.com/OliveTin/OliveTin"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
],
"summary": "OliveTin has unauthenticated DoS via concurrent map writes in OAuth2 state handling"
}
GHSA-4H4V-HCR3-CJC9
Vulnerability from github – Published: 2023-02-06 21:30 – Updated: 2023-02-14 18:30In ccu, there is a possible memory corruption due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS07512839; Issue ID: ALPS07512839.
{
"affected": [],
"aliases": [
"CVE-2023-20607"
],
"database_specific": {
"cwe_ids": [
"CWE-662"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-02-06T20:15:00Z",
"severity": "MODERATE"
},
"details": "In ccu, there is a possible memory corruption due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS07512839; Issue ID: ALPS07512839.",
"id": "GHSA-4h4v-hcr3-cjc9",
"modified": "2023-02-14T18:30:21Z",
"published": "2023-02-06T21:30:33Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-20607"
},
{
"type": "WEB",
"url": "https://corp.mediatek.com/product-security-bulletin/February-2023"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-4RJ3-H5C4-JPRH
Vulnerability from github – Published: 2023-12-05 18:30 – Updated: 2023-12-05 18:30An issue exists in SoftIron HyperCloud where drive caddy removal and reinsertion without a reboot may erroneously cause the system to recognize the caddy as new media and wipe all data on the drives due to a missing synchronization flaw, which impacts data availability and integrity.
This issue only impacts SoftIron HyperCloud "density" storage nodes running HyperCloud software versions 1.0 to before 2.0.3.
{
"affected": [],
"aliases": [
"CVE-2023-45084"
],
"database_specific": {
"cwe_ids": [
"CWE-662",
"CWE-820"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-12-05T17:15:08Z",
"severity": "HIGH"
},
"details": "An issue exists in SoftIron HyperCloud where drive caddy removal and reinsertion without a reboot may erroneously cause the system to recognize the caddy as new media and wipe all data on the drives due to a missing synchronization flaw, which impacts data availability and integrity.\n\nThis issue only impacts SoftIron HyperCloud \"density\" storage nodes running HyperCloud software versions 1.0 to before 2.0.3.\n\n",
"id": "GHSA-4rj3-h5c4-jprh",
"modified": "2023-12-05T18:30:23Z",
"published": "2023-12-05T18:30:23Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-45084"
},
{
"type": "WEB",
"url": "https://advisories.softiron.cloud"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-4RX3-CPGG-X277
Vulnerability from github – Published: 2022-06-01 00:00 – Updated: 2022-06-09 00:00Incorrect Synchronization in GitHub repository polonel/trudesk prior to 1.2.3.
{
"affected": [],
"aliases": [
"CVE-2022-1931"
],
"database_specific": {
"cwe_ids": [
"CWE-662"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-05-31T02:15:00Z",
"severity": "HIGH"
},
"details": "Incorrect Synchronization in GitHub repository polonel/trudesk prior to 1.2.3.",
"id": "GHSA-4rx3-cpgg-x277",
"modified": "2022-06-09T00:00:18Z",
"published": "2022-06-01T00:00:40Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-1931"
},
{
"type": "WEB",
"url": "https://github.com/polonel/trudesk/commit/314540864dbf2c0eaa99aa42c3d317de9501eb67"
},
{
"type": "WEB",
"url": "https://huntr.dev/bounties/50c4cb63-65db-41c5-a16d-0560d7131fde"
}
],
"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:N",
"type": "CVSS_V3"
}
]
}
GHSA-5VV4-4CPW-9C7V
Vulnerability from github – Published: 2023-01-03 21:30 – Updated: 2023-01-10 03:30In vow, there is a possible use after free due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS07494473; Issue ID: ALPS07494473.
{
"affected": [],
"aliases": [
"CVE-2022-32644"
],
"database_specific": {
"cwe_ids": [
"CWE-662"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-01-03T21:15:00Z",
"severity": "MODERATE"
},
"details": "In vow, there is a possible use after free due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS07494473; Issue ID: ALPS07494473.",
"id": "GHSA-5vv4-4cpw-9c7v",
"modified": "2023-01-10T03:30:28Z",
"published": "2023-01-03T21:30:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-32644"
},
{
"type": "WEB",
"url": "https://corp.mediatek.com/product-security-bulletin/January-2023"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-62CG-XHWR-XF37
Vulnerability from github – Published: 2023-04-11 21:31 – Updated: 2025-10-22 00:32Windows CNG Key Isolation Service Elevation of Privilege Vulnerability
{
"affected": [],
"aliases": [
"CVE-2023-28229"
],
"database_specific": {
"cwe_ids": [
"CWE-591",
"CWE-662"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-04-11T21:15:00Z",
"severity": "HIGH"
},
"details": "Windows CNG Key Isolation Service Elevation of Privilege Vulnerability",
"id": "GHSA-62cg-xhwr-xf37",
"modified": "2025-10-22T00:32:43Z",
"published": "2023-04-11T21:31:01Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-28229"
},
{
"type": "WEB",
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-28229"
},
{
"type": "WEB",
"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-28229"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-6366-2H38-JF23
Vulnerability from github – Published: 2023-01-03 21:30 – Updated: 2023-01-10 03:30In vow, there is a possible information disclosure due to a race condition. This could lead to local information disclosure with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS07494477; Issue ID: ALPS07494477.
{
"affected": [],
"aliases": [
"CVE-2022-32645"
],
"database_specific": {
"cwe_ids": [
"CWE-362",
"CWE-662"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-01-03T21:15:00Z",
"severity": "MODERATE"
},
"details": "In vow, there is a possible information disclosure due to a race condition. This could lead to local information disclosure with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS07494477; Issue ID: ALPS07494477.",
"id": "GHSA-6366-2h38-jf23",
"modified": "2023-01-10T03:30:28Z",
"published": "2023-01-03T21:30:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-32645"
},
{
"type": "WEB",
"url": "https://corp.mediatek.com/product-security-bulletin/January-2023"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
Mitigation
Use industry standard APIs to synchronize your code.
CAPEC-25: Forced Deadlock
The adversary triggers and exploits a deadlock condition in the target software to cause a denial of service. A deadlock can occur when two or more competing actions are waiting for each other to finish, and thus neither ever does. Deadlock conditions can be difficult to detect.
CAPEC-26: Leveraging Race Conditions
The adversary targets a race condition occurring when multiple processes access and manipulate the same resource concurrently, and the outcome of the execution depends on the particular order in which the access takes place. The adversary can leverage a race condition by "running the race", modifying the resource and modifying the normal execution flow. For instance, a race condition can occur while accessing a file: the adversary can trick the system by replacing the original file with their version and cause the system to read the malicious file.
CAPEC-27: Leveraging Race Conditions via Symbolic Links
This attack leverages the use of symbolic links (Symlinks) in order to write to sensitive files. An attacker can create a Symlink link to a target file not otherwise accessible to them. When the privileged program tries to create a temporary file with the same name as the Symlink link, it will actually write to the target file pointed to by the attackers' Symlink link. If the attacker can insert malicious content in the temporary file they will be writing to the sensitive file by using the Symlink. The race occurs because the system checks if the temporary file exists, then creates the file. The attacker would typically create the Symlink during the interval between the check and the creation of the temporary file.
CAPEC-29: Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions
This attack targets a race condition occurring between the time of check (state) for a resource and the time of use of a resource. A typical example is file access. The adversary can leverage a file access race condition by "running the race", meaning that they would modify the resource between the first time the target program accesses the file and the time the target program uses the file. During that period of time, the adversary could replace or modify the file, causing the application to behave unexpectedly.