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FKIE_CVE-2026-19591

Vulnerability from fkie_nvd - Published: 2026-09-01 18:17 - Updated: 2026-09-02 19:17
Severity
8.8 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Summary
OpenAI Codex CLI for Windows, macOS, and Linux and Codex Desktop for Windows and macOS misclassified certain PowerShell commands as safe because their command-safety parser interpreted PowerShell's stop-parsing token (--%) differently than PowerShell itself. If a user opens an attacker-prepared repository and Codex follows its instructions, Codex can run a file-writing Git command without requesting user approval. On macOS and Linux, exploitation additionally requires separately installed PowerShell Core (pwsh) to be invoked. If filesystem protections permit the write, the command can modify Codex's configuration. If Codex later loads the modified configuration, it can launch an attacker-controlled MCP server and execute code with the user's privileges, allowing it to read, change, or delete files accessible to that account. The approval bypass does not disable filesystem sandboxing; the default filesystem sandbox on macOS and Linux can prevent writes outside permitted locations.
References
8f4f43ab-ba69-4d92-aa1d-d772184d6fb7https://github.com/openai/codex/pull/22643
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "platforms": [
            "Windows",
            "macOS",
            "Linux"
          ],
          "product": "Codex CLI",
          "vendor": "OpenAI",
          "versions": [
            {
              "lessThanOrEqual": "0.130.0",
              "status": "affected",
              "version": "0.72.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "0.131.0"
            }
          ]
        },
        {
          "platforms": [
            "macOS"
          ],
          "product": "Codex Desktop",
          "vendor": "OpenAI",
          "versions": [
            {
              "lessThanOrEqual": "26.513.31313",
              "status": "affected",
              "version": "260202.0859",
              "versionType": "custom"
            },
            {
              "status": "unaffected",
              "version": "26.519.22136"
            }
          ]
        },
        {
          "platforms": [
            "Windows"
          ],
          "product": "Codex Desktop",
          "vendor": "OpenAI",
          "versions": [
            {
              "lessThanOrEqual": "26.513.40821",
              "status": "affected",
              "version": "26.304.38",
              "versionType": "custom"
            },
            {
              "status": "unaffected",
              "version": "26.519.21041"
            }
          ]
        },
        {
          "platforms": [
            "Windows"
          ],
          "product": "Codex Desktop (Microsoft Store package)",
          "vendor": "OpenAI",
          "versions": [
            {
              "lessThanOrEqual": "26.513.4821.0",
              "status": "affected",
              "version": "26.304.38.0",
              "versionType": "custom"
            },
            {
              "status": "unaffected",
              "version": "26.519.2081.0"
            }
          ]
        }
      ],
      "source": "8f4f43ab-ba69-4d92-aa1d-d772184d6fb7"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "OpenAI Codex CLI for Windows, macOS, and Linux and Codex Desktop for Windows and macOS misclassified certain PowerShell commands as safe because their command-safety parser interpreted PowerShell\u0027s stop-parsing token (--%) differently than PowerShell itself. If a user opens an attacker-prepared repository and Codex follows its instructions, Codex can run a file-writing Git command without requesting user approval. On macOS and Linux, exploitation additionally requires separately installed PowerShell Core (pwsh) to be invoked. If filesystem protections permit the write, the command can modify Codex\u0027s configuration. If Codex later loads the modified configuration, it can launch an attacker-controlled MCP server and execute code with the user\u0027s privileges, allowing it to read, change, or delete files accessible to that account. The approval bypass does not disable filesystem sandboxing; the default filesystem sandbox on macOS and Linux can prevent writes outside permitted locations."
    }
  ],
  "id": "CVE-2026-19591",
  "lastModified": "2026-09-02T19:17:16.760",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-19591",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-02T18:34:17.952844Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-01T18:17:40.260",
  "references": [
    {
      "source": "8f4f43ab-ba69-4d92-aa1d-d772184d6fb7",
      "url": "https://github.com/openai/codex/pull/22643"
    }
  ],
  "sourceIdentifier": "8f4f43ab-ba69-4d92-aa1d-d772184d6fb7",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-150"
        }
      ],
      "source": "8f4f43ab-ba69-4d92-aa1d-d772184d6fb7",
      "type": "Secondary"
    }
  ]
}



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