CVE-2026-19591 (GCVE-0-2026-19591)

Vulnerability from cvelistv5 – Published: 2026-09-01 17:06 – Updated: 2026-09-01 17:06
VLAI
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.
Severity
No CVSS data available.
CWE
  • CWE-150 - Improper Neutralization of Escape, Meta, or Control Sequences
Assigner
References
Impacted products
Vendor Product Version CPE status
OpenAI Codex CLI Affected: 0.72.0 , ≤ 0.130.0 (semver)
Unaffected: 0.131.0
guessed Create a notification for this product.
OpenAI Codex Desktop Affected: 260202.0859 , ≤ 26.513.31313 (custom)
Unaffected: 26.519.22136
guessed Create a notification for this product.
OpenAI Codex Desktop Affected: 26.304.38 , ≤ 26.513.40821 (custom)
Unaffected: 26.519.21041
guessed Create a notification for this product.
OpenAI Codex Desktop (Microsoft Store package) Affected: 26.304.38.0 , ≤ 26.513.4821.0 (custom)
Unaffected: 26.519.2081.0
guessed Create a notification for this product.
Credits
Emanuele Barbeno, Cyrill Bannwart, Yves Bieri, Lukasz D., and Urs Mueller of Compass Security (@compasssecurity).
Show details on NVD website
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{
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        }
      ],
      "problemTypes": [
        {
          "descriptions": [
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              "cweId": "CWE-150",
              "description": "CWE-150: Improper Neutralization of Escape, Meta, or Control Sequences",
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        "orgId": "8f4f43ab-ba69-4d92-aa1d-d772184d6fb7",
        "shortName": "OAI"
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      "references": [
        {
          "url": "https://github.com/openai/codex/pull/22643"
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      "solutions": [
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          "lang": "en",
          "value": "Upgrade Codex CLI to version 0.131.0 or later, Codex Desktop for macOS to application version 26.519.22136 or later, or Codex Desktop for Windows to application version 26.519.21041 (Microsoft Store package 26.519.2081.0) or later."
        }
      ],
      "workarounds": [
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          "value": "Until updated, do not open or follow instructions from untrusted repositories. On macOS and Linux, keep filesystem sandboxing enabled."
        }
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    "datePublished": "2026-09-01T17:06:45.647Z",
    "dateReserved": "2026-08-12T03:54:33.704Z",
    "dateUpdated": "2026-09-01T17:06:45.647Z",
    "state": "PUBLISHED"
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  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.