Common Weakness Enumeration

CWE-367

Allowed

Time-of-check Time-of-use (TOCTOU) Race Condition

Abstraction: Base · Status: Incomplete

API response cwe.mitre.org

The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.

1063 vulnerabilities reference this CWE, most recent first.

GHSA-MVJP-6VJ8-PMX6

Vulnerability from github – Published: 2023-10-25 18:32 – Updated: 2023-10-25 18:32
VLAI
Details

A logged in user may elevate its permissions by abusing a Time-of-Check to Time-of-Use (TOCTOU) race condition. When a particular process flow is initiated, an attacker can exploit this condition to gain unauthorized elevated privileges on the affected system.

Severity
7.8 (High)
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2023-38041"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-10-25T18:17:28Z",
    "severity": "HIGH"
  },
  "details": "A logged in user may elevate its permissions by abusing a Time-of-Check to Time-of-Use (TOCTOU) race condition. When a particular process flow is initiated, an attacker can exploit this condition to gain unauthorized elevated privileges on the affected system.",
  "id": "GHSA-mvjp-6vj8-pmx6",
  "modified": "2023-10-25T18:32:21Z",
  "published": "2023-10-25T18:32:21Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-38041"
    },
    {
      "type": "WEB",
      "url": "https://forums.ivanti.com/s/article/CVE-2023-38041-New-client-side-release-to-address-a-privilege-escalation-on-Windows-user-machines?language=en_US"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-MW5V-W29J-C9G9

Vulnerability from github – Published: 2023-01-09 09:30 – Updated: 2023-01-13 03:30
VLAI
Details

Memory corruption in Multimedia Framework due to unsafe access to the data members

Severity
7.0 (High)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2022-25716"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-01-09T08:15:00Z",
    "severity": "HIGH"
  },
  "details": "Memory corruption in Multimedia Framework due to unsafe access to the data members",
  "id": "GHSA-mw5v-w29j-c9g9",
  "modified": "2023-01-13T03:30:19Z",
  "published": "2023-01-09T09:30:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-25716"
    },
    {
      "type": "WEB",
      "url": "https://www.qualcomm.com/company/product-security/bulletins/january-2023-bulletin"
    }
  ],
  "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-MWCG-WFQ3-4GJC

Vulnerability from github – Published: 2026-03-03 19:18 – Updated: 2026-03-30 13:34
VLAI
Summary
OpenClaw's system.run approval TOCTOU via mutable symlink cwd target on node host
Details

Summary

In openclaw@2026.2.24, approval-bound system.run on node hosts could be influenced by mutable symlink cwd targets between approval and execution.

Details

Approval matching on the gateway validated command/argv and binding fields, including cwd, as provided text. Node execution later used runtime cwd resolution. A symlinked cwd could therefore be retargeted after approval and before spawn.

OpenClaw's trust model does not treat one shared gateway as a multi-tenant adversarial boundary, but approval integrity is still a security boundary for operator-reviewed command execution.

Affected Packages / Versions

  • Package: openclaw (npm)
  • Affected: <= 2026.2.24
  • Patched: >= 2026.2.25

Fix Commit(s)

  • f789f880c934caa8be25b38832f27f90f37903db

Remediation

The fix adds defense-in-depth hardening for approval-bound node execution: - reject symlink cwd paths for approval-bound system.run - canonicalize path-like executable argv before spawn - bind CLI approval requests to exact commandArgv

Release Process Note

Patched version is pre-set to the release (2026.2.25). Advisory published with npm release 2026.2.25.

OpenClaw thanks @tdjackey for reporting.

Severity
5.9 (Medium)
CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:L/VI:H/VA:H/SC:N/SI:N/SA:N
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2026.2.24"
      },
      "package": {
        "ecosystem": "npm",
        "name": "openclaw"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2026.2.25"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-32043"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367",
      "CWE-59"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-03T19:18:06Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Summary\nIn `openclaw@2026.2.24`, approval-bound `system.run` on node hosts could be influenced by mutable symlink `cwd` targets between approval and execution.\n\n### Details\nApproval matching on the gateway validated command/argv and binding fields, including `cwd`, as provided text. Node execution later used runtime `cwd` resolution. A symlinked `cwd` could therefore be retargeted after approval and before spawn.\n\nOpenClaw\u0027s trust model does not treat one shared gateway as a multi-tenant adversarial boundary, but approval integrity is still a security boundary for operator-reviewed command execution.\n\n### Affected Packages / Versions\n- Package: `openclaw` (npm)\n- Affected: `\u003c= 2026.2.24`\n- Patched: `\u003e= 2026.2.25` \n\n### Fix Commit(s)\n- `f789f880c934caa8be25b38832f27f90f37903db`\n\n### Remediation\nThe fix adds defense-in-depth hardening for approval-bound node execution:\n- reject symlink `cwd` paths for approval-bound `system.run`\n- canonicalize path-like executable argv before spawn\n- bind CLI approval requests to exact `commandArgv`\n\n### Release Process Note\nPatched version is pre-set to the release (`2026.2.25`). Advisory published with npm release `2026.2.25`.\n\nOpenClaw thanks @tdjackey for reporting.",
  "id": "GHSA-mwcg-wfq3-4gjc",
  "modified": "2026-03-30T13:34:50Z",
  "published": "2026-03-03T19:18:06Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-mwcg-wfq3-4gjc"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-32043"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openclaw/openclaw/commit/f789f880c934caa8be25b38832f27f90f37903db"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/openclaw/openclaw"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/openclaw-time-of-check-time-of-use-via-mutable-symlink-in-system-run-cwd-parameter"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:L/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "OpenClaw\u0027s system.run approval TOCTOU via mutable symlink cwd target on node host"
}

GHSA-MWCQ-W75H-9P3W

Vulnerability from github – Published: 2022-05-24 17:28 – Updated: 2022-05-24 17:28
VLAI
Details

In SurfaceFlinger, 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.Product: AndroidVersions: Android-11Android ID: A-150227563

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{
  "affected": [],
  "aliases": [
    "CVE-2020-0358"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-09-17T21:15:00Z",
    "severity": "MODERATE"
  },
  "details": "In SurfaceFlinger, 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.Product: AndroidVersions: Android-11Android ID: A-150227563",
  "id": "GHSA-mwcq-w75h-9p3w",
  "modified": "2022-05-24T17:28:46Z",
  "published": "2022-05-24T17:28:46Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-0358"
    },
    {
      "type": "WEB",
      "url": "https://source.android.com/security/bulletin/android-11"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-MWV9-723W-9F8R

Vulnerability from github – Published: 2025-02-03 18:30 – Updated: 2025-02-03 18:30
VLAI
Details

Memory corruption while taking a snapshot with hardware encoder due to unvalidated userspace buffer.

Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2024-45560"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-02-03T17:15:18Z",
    "severity": "HIGH"
  },
  "details": "Memory corruption while taking a snapshot with hardware encoder due to unvalidated userspace buffer.",
  "id": "GHSA-mwv9-723w-9f8r",
  "modified": "2025-02-03T18:30:42Z",
  "published": "2025-02-03T18:30:42Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-45560"
    },
    {
      "type": "WEB",
      "url": "https://docs.qualcomm.com/product/publicresources/securitybulletin/february-2025-bulletin.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"
    }
  ]
}

GHSA-MX29-FW97-M6GR

Vulnerability from github – Published: 2026-05-27 15:33 – Updated: 2026-06-25 15:31
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

bpf: Require frozen map for calculating map hash

Currently, bpf_map_get_info_by_fd calculates and caches the hash of the map regardless of the map's frozen state.

This leads to a TOCTOU bug where userspace can call BPF_OBJ_GET_INFO_BY_FD to cache the hash and then modify the map contents before freezing.

Therefore, a trusted loader can be tricked into verifying the stale hash while loading the modified contents.

Fix this by returning -EPERM if the map is not frozen when the hash is requested. This ensures the hash is only generated for the final, immutable state of the map.

Severity
4.7 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2026-45927"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-27T14:17:08Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Require frozen map for calculating map hash\n\nCurrently, bpf_map_get_info_by_fd calculates and caches the hash of the\nmap regardless of the map\u0027s frozen state.\n\nThis leads to a TOCTOU bug where userspace can call\nBPF_OBJ_GET_INFO_BY_FD to cache the hash and then modify the map\ncontents before freezing.\n\nTherefore, a trusted loader can be tricked into verifying the stale hash\nwhile loading the modified contents.\n\nFix this by returning -EPERM if the map is not frozen when the hash is\nrequested. This ensures the hash is only generated for the final,\nimmutable state of the map.",
  "id": "GHSA-mx29-fw97-m6gr",
  "modified": "2026-06-25T15:31:43Z",
  "published": "2026-05-27T15:33:16Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45927"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7752d36343862323bbeea4ce3adf0ec2ed86e122"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a2c86aa621c22f2a7e26c654f936d65cfff0aa91"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f415e114b58fe02c41191e47f24bdabb438daf72"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-MXC8-4JQF-368Q

Vulnerability from github – Published: 2026-01-23 18:31 – Updated: 2026-01-23 20:16
VLAI
Summary
miniserve affected by a TOCTOU and symlink race vulnerability
Details

A TOCTOU and symlink race in svenstaro/miniserve 0.32.0 upload finalization (when uploads are enabled) can allow an attacker to overwrite arbitrary files outside the intended upload/document root in deployments where the attacker can create/replace filesystem entries in the upload destination directory (e.g., shared writable directory/volume).

Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
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{
  "affected": [
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "miniserve"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.32.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-67124"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367",
      "CWE-59"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-23T20:16:21Z",
    "nvd_published_at": "2026-01-23T16:15:52Z",
    "severity": "MODERATE"
  },
  "details": "A TOCTOU and symlink race in svenstaro/miniserve 0.32.0 upload finalization (when uploads are enabled) can allow an attacker to overwrite arbitrary files outside the intended upload/document root in deployments where the attacker can create/replace filesystem entries in the upload destination directory (e.g., shared writable directory/volume).",
  "id": "GHSA-mxc8-4jqf-368q",
  "modified": "2026-01-23T20:16:21Z",
  "published": "2026-01-23T18:31:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-67124"
    },
    {
      "type": "WEB",
      "url": "https://gist.github.com/thesmartshadow/55688f87f8b985eb530e07d00ef8c63f"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/svenstaro/miniserve"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "miniserve affected by a TOCTOU and symlink race vulnerability"
}

GHSA-P22W-HM7X-WWFC

Vulnerability from github – Published: 2023-02-27 21:30 – Updated: 2023-03-08 18:30
VLAI
Details

A race condition was addressed with additional validation. This issue is fixed in macOS Ventura 13.2, iOS 16.3 and iPadOS 16.3. A user may be able to read arbitrary files as root.

Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
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{
  "affected": [],
  "aliases": [
    "CVE-2023-23520"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-02-27T20:15:00Z",
    "severity": "MODERATE"
  },
  "details": "A race condition was addressed with additional validation. This issue is fixed in macOS Ventura 13.2, iOS 16.3 and iPadOS 16.3. A user may be able to read arbitrary files as root.",
  "id": "GHSA-p22w-hm7x-wwfc",
  "modified": "2023-03-08T18:30:26Z",
  "published": "2023-02-27T21:30:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-23520"
    },
    {
      "type": "WEB",
      "url": "https://support.apple.com/en-us/HT213599"
    },
    {
      "type": "WEB",
      "url": "https://support.apple.com/en-us/HT213601"
    },
    {
      "type": "WEB",
      "url": "https://support.apple.com/en-us/HT213605"
    },
    {
      "type": "WEB",
      "url": "https://support.apple.com/en-us/HT213606"
    },
    {
      "type": "WEB",
      "url": "https://support.apple.com/kb/HT213599"
    },
    {
      "type": "WEB",
      "url": "https://support.apple.com/kb/HT213601"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-P293-86CR-RJ34

Vulnerability from github – Published: 2025-03-07 18:31 – Updated: 2025-03-07 18:31
VLAI
Details

A time-of-check time-of-use (TOCTOU) race condition vulnerability has been reported to affect several product versions. If exploited, the vulnerability could allow local attackers who have gained user access to gain access to otherwise unauthorized resources.

We have already fixed the vulnerability in the following versions: QVPN Device Client for Mac 2.2.5 and later Qsync for Mac 5.1.3 and later Qfinder Pro Mac 7.11.1 and later

Severity
8.6 (High)
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
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{
  "affected": [],
  "aliases": [
    "CVE-2024-53694"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-03-07T17:15:20Z",
    "severity": "HIGH"
  },
  "details": "A time-of-check time-of-use (TOCTOU) race condition vulnerability has been reported to affect several product versions. If exploited, the vulnerability could allow local attackers who have gained user access to gain access to otherwise unauthorized resources.\n\nWe have already fixed the vulnerability in the following versions:\nQVPN Device Client for Mac 2.2.5 and later\nQsync for Mac 5.1.3 and later\nQfinder Pro Mac 7.11.1 and later",
  "id": "GHSA-p293-86cr-rj34",
  "modified": "2025-03-07T18:31:06Z",
  "published": "2025-03-07T18:31:05Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-53694"
    },
    {
      "type": "WEB",
      "url": "https://www.qnap.com/en/security-advisory/qsa-24-51"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/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-P2M9-83F8-9277

Vulnerability from github – Published: 2022-05-24 17:23 – Updated: 2022-05-24 17:23
VLAI
Details

Vulnerability in the Oracle VM VirtualBox product of Oracle Virtualization (component: Core). Supported versions that are affected are Prior to 5.2.44, prior to 6.0.24 and prior to 6.1.12. Difficult to exploit vulnerability allows high privileged attacker with logon to the infrastructure where Oracle VM VirtualBox executes to compromise Oracle VM VirtualBox. While the vulnerability is in Oracle VM VirtualBox, attacks may significantly impact additional products. Successful attacks of this vulnerability can result in takeover of Oracle VM VirtualBox. CVSS 3.1 Base Score 7.5 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H).

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{
  "affected": [],
  "aliases": [
    "CVE-2020-14677"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-07-15T18:15:00Z",
    "severity": "MODERATE"
  },
  "details": "Vulnerability in the Oracle VM VirtualBox product of Oracle Virtualization (component: Core). Supported versions that are affected are Prior to 5.2.44, prior to 6.0.24 and prior to 6.1.12. Difficult to exploit vulnerability allows high privileged attacker with logon to the infrastructure where Oracle VM VirtualBox executes to compromise Oracle VM VirtualBox. While the vulnerability is in Oracle VM VirtualBox, attacks may significantly impact additional products. Successful attacks of this vulnerability can result in takeover of Oracle VM VirtualBox. CVSS 3.1 Base Score 7.5 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H).",
  "id": "GHSA-p2m9-83f8-9277",
  "modified": "2022-05-24T17:23:31Z",
  "published": "2022-05-24T17:23:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-14677"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/202101-09"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpujul2020.html"
    },
    {
      "type": "WEB",
      "url": "https://www.zerodayinitiative.com/advisories/ZDI-20-893"
    },
    {
      "type": "WEB",
      "url": "http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00068.html"
    },
    {
      "type": "WEB",
      "url": "http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00079.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}
Mitigation
Implementation

The most basic advice for TOCTOU vulnerabilities is to not perform a check before the use. This does not resolve the underlying issue of the execution of a function on a resource whose state and identity cannot be assured, but it does help to limit the false sense of security given by the check.

Mitigation
Implementation

When the file being altered is owned by the current user and group, set the effective gid and uid to that of the current user and group when executing this statement.

Mitigation
Architecture and Design

Limit the interleaving of operations on files from multiple processes.

Mitigation
Implementation Architecture and Design

If you cannot perform operations atomically and you must share access to the resource between multiple processes or threads, then try to limit the amount of time (CPU cycles) between the check and use of the resource. This will not fix the problem, but it could make it more difficult for an attack to succeed.

Mitigation
Implementation

Recheck the resource after the use call to verify that the action was taken appropriately.

Mitigation
Architecture and Design

Ensure that some environmental locking mechanism can be used to protect resources effectively.

Mitigation
Implementation

Ensure that locking occurs before the check, as opposed to afterwards, such that the resource, as checked, is the same as it is when in use.

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.

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