CVE-2026-96644 (GCVE-0-2026-96644)

Vulnerability from cvelistv5 – Published: 2026-10-21 20:54 – Updated: 2026-10-21 20:54
VLAI
Title
Pillow: Heap over-read in WMF/EMF rendering via 16-bit dimension truncation (Windows builds)
Summary
Pillow is a Python imaging library. Prior to 13.0.0 on Windows, src/PIL/WmfImagePlugin.py passes unchecked 32-bit WMF or EMF dimensions to the native drawwmf handler in src/display.c. The handler sizes a DIB allocation from 16-bit-truncated bcWidth and bcHeight fields but copies pixel data using the original full dimensions. A crafted wide, short metafile can pass the pixel-count decompression-bomb check and make the Windows-only renderer read beyond the heap buffer, potentially disclosing memory or crashing the process. This issue is fixed in version 13.0.0.
Severity
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7734 records in the last 180 days details
References
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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        }
      ],
      "metrics": [
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            "attackRequirements": "NONE",
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            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "PASSIVE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N",
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            "vulnIntegrityImpact": "NONE"
          }
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      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-125",
              "description": "CWE-125: Out-of-bounds Read",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-21T20:54:43.537Z",
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        "shortName": "GitHub_M"
      },
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          "name": "https://github.com/python-pillow/Pillow/security/advisories/GHSA-9v9v-9qvf-h2hj",
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          "url": "https://github.com/python-pillow/Pillow/security/advisories/GHSA-9v9v-9qvf-h2hj"
        },
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          "url": "https://github.com/python-pillow/Pillow/pull/10120"
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          "tags": [
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          "url": "https://github.com/python-pillow/Pillow/commit/4cf46bee338304c5c8968fd7f132ba0d40c428b7"
        },
        {
          "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"
        }
      ],
      "source": {
        "advisory": "GHSA-9v9v-9qvf-h2hj",
        "discovery": "UNKNOWN"
      },
      "title": "Pillow: Heap over-read in WMF/EMF rendering via 16-bit dimension truncation (Windows builds)"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-96644",
    "datePublished": "2026-10-21T20:54:43.537Z",
    "dateReserved": "2026-09-23T14:35:50.130Z",
    "dateUpdated": "2026-10-21T20:54:43.537Z",
    "state": "PUBLISHED"
  },
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      "epss": "0.00333",
      "percentile": "0.25364"
    },
    "nvd": {
      "cve": {
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                "vendor": "python-pillow",
                "versions": [
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                    "version": "\u003c 13.0.0"
                  }
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        "cveTags": [],
        "descriptions": [
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            "value": "Pillow is a Python imaging library. Prior to 13.0.0 on Windows, src/PIL/WmfImagePlugin.py passes unchecked 32-bit WMF or EMF dimensions to the native drawwmf handler in src/display.c. The handler sizes a DIB allocation from 16-bit-truncated bcWidth and bcHeight fields but copies pixel data using the original full dimensions. A crafted wide, short metafile can pass the pixel-count decompression-bomb check and make the Windows-only renderer read beyond the heap buffer, potentially disclosing memory or crashing the process. This issue is fixed in version 13.0.0."
          }
        ],
        "id": "CVE-2026-96644",
        "lastModified": "2026-10-22T16:46:48.920",
        "metrics": {
          "cvssMetricV40": [
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                "Recovery": "NOT_DEFINED",
                "Safety": "NOT_DEFINED",
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                "attackVector": "NETWORK",
                "availabilityRequirement": "NOT_DEFINED",
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                "baseSeverity": "HIGH",
                "confidentialityRequirement": "NOT_DEFINED",
                "exploitMaturity": "NOT_DEFINED",
                "integrityRequirement": "NOT_DEFINED",
                "modifiedAttackComplexity": "NOT_DEFINED",
                "modifiedAttackRequirements": "NOT_DEFINED",
                "modifiedAttackVector": "NOT_DEFINED",
                "modifiedPrivilegesRequired": "NOT_DEFINED",
                "modifiedSubAvailabilityImpact": "NOT_DEFINED",
                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
                "modifiedUserInteraction": "NOT_DEFINED",
                "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
                "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
                "modifiedVulnIntegrityImpact": "NOT_DEFINED",
                "privilegesRequired": "NONE",
                "providerUrgency": "NOT_DEFINED",
                "subAvailabilityImpact": "NONE",
                "subConfidentialityImpact": "NONE",
                "subIntegrityImpact": "NONE",
                "userInteraction": "PASSIVE",
                "valueDensity": "NOT_DEFINED",
                "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/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",
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              "type": "Secondary"
            }
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        "references": [
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            "url": "https://github.com/python-pillow/Pillow/commit/4cf46bee338304c5c8968fd7f132ba0d40c428b7"
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        "vulnStatus": "Undergoing Analysis",
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    },
    "redhat_vex": {
      "aggregate_severity": "Important",
      "current_release_date": "2026-10-23T16:33:38+00:00",
      "cve": "CVE-2026-96644",
      "id": "CVE-2026-96644",
      "initial_release_date": "2026-10-21T20:54:43.537000+00:00",
      "product_status:known_affected": "88",
      "product_status:known_not_affected": "6",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "pillow: Pillow: Denial of Service via out-of-bounds read in metafile parser",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-96644.json",
      "version": "3"
    }
  }
}



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