CVE-2026-96642 (GCVE-0-2026-96642)

Vulnerability from cvelistv5 – Published: 2026-10-21 20:49 – Updated: 2026-10-21 20:49
VLAI
Title
Pillow: TarIO negative size field causes infinite CPU-spin loop
Summary
Pillow is a Python imaging library. Prior to 13.0.0, the TarIO initializer in src/PIL/TarIO.py accepts a negative octal member size and computes a backward seek that returns to the same 512-byte header. When the requested member name does not match, the parser repeatedly reads that header, consumes a full CPU core, and never returns. TarIO is reached only when an application directly uses PIL.TarIO.TarIO rather than the default Image.open() path. This issue is fixed in version 13.0.0.
CWE
  • CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7640 records in the last 180 days details
Impacted products
Vendor Product Version CPE status
python-pillow Pillow Affected: < 13.0.0
guessed Create a notification for this product.
Show details on NVD website

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        }
      ],
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              "cweId": "CWE-835",
              "description": "CWE-835: Loop with Unreachable Exit Condition (\u0027Infinite Loop\u0027)",
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              "type": "CWE"
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        "dateUpdated": "2026-10-21T20:49:56.989Z",
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          "name": "https://github.com/python-pillow/Pillow/security/advisories/GHSA-3j72-p6qg-6xp7",
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          "url": "https://github.com/python-pillow/Pillow/security/advisories/GHSA-3j72-p6qg-6xp7"
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          "name": "https://github.com/python-pillow/Pillow/releases/tag/13.0.0",
          "tags": [
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          "url": "https://github.com/python-pillow/Pillow/releases/tag/13.0.0"
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      "source": {
        "advisory": "GHSA-3j72-p6qg-6xp7",
        "discovery": "UNKNOWN"
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      "title": "Pillow: TarIO negative size field causes infinite CPU-spin loop"
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  "cveMetadata": {
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    "datePublished": "2026-10-21T20:49:56.989Z",
    "dateReserved": "2026-09-23T14:35:50.130Z",
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                    "version": "\u003c 13.0.0"
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          }
        ],
        "id": "CVE-2026-96642",
        "lastModified": "2026-10-22T16:46:48.920",
        "metrics": {
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                "modifiedAttackRequirements": "NOT_DEFINED",
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                "modifiedPrivilegesRequired": "NOT_DEFINED",
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                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
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                "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
                "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
                "modifiedVulnIntegrityImpact": "NOT_DEFINED",
                "privilegesRequired": "NONE",
                "providerUrgency": "NOT_DEFINED",
                "subAvailabilityImpact": "NONE",
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                "valueDensity": "NOT_DEFINED",
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      "cve": "CVE-2026-96642",
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      "initial_release_date": "2026-10-21T20:49:56.989000+00:00",
      "product_status:known_affected": "94",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "pillow: Pillow: Denial of Service via negative archive member size in TarIO",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-96642.json",
      "version": "3"
    }
  }
}



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