GHSA-WHJ4-6X5X-4V2J

Vulnerability from github – Published: 2026-04-13 19:22 – Updated: 2026-04-16 21:56
VLAI?
Summary
FITS GZIP decompression bomb in Pillow
Details

Impact

Pillow did not limit the amount of GZIP-compressed data read when decoding a FITS image, making it vulnerable to decompression bomb attacks. A specially crafted FITS file could cause unbounded memory consumption, leading to denial of service (OOM crash or severe performance degradation).

Patches

The amount of data read is now limited to the necessary amount. Fixed in Pillow 12.2.0 (PR #9521).

Workarounds

Avoid Pillow >= 10.3.0, < 12.2.0 Only open specific image formats, excluding FITS.

Severity ?
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "pillow"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "10.3.0"
            },
            {
              "fixed": "12.2.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40192"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-13T19:22:35Z",
    "nvd_published_at": "2026-04-15T23:16:10Z",
    "severity": "HIGH"
  },
  "details": "### Impact\nPillow did not limit the amount of GZIP-compressed data read when decoding a FITS image, making it vulnerable to decompression bomb attacks. A specially crafted FITS file could cause unbounded memory consumption, leading to denial of service (OOM crash or severe performance degradation).\n\n### Patches\nThe amount of data read is now limited to the necessary amount.\nFixed in Pillow 12.2.0 (PR #9521).\n\n### Workarounds\nAvoid Pillow \u003e= 10.3.0, \u003c 12.2.0\nOnly open [specific image formats](https://pillow.readthedocs.io/en/stable/releasenotes/8.0.0.html#image-open-add-formats-parameter), excluding FITS.",
  "id": "GHSA-whj4-6x5x-4v2j",
  "modified": "2026-04-16T21:56:27Z",
  "published": "2026-04-13T19:22:35Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/python-pillow/Pillow/security/advisories/GHSA-whj4-6x5x-4v2j"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40192"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python-pillow/Pillow/pull/9521"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python-pillow/Pillow/commit/3cb854e8b2bab43f40e342e665f9340d861aa628"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/python-pillow/Pillow"
    },
    {
      "type": "WEB",
      "url": "https://pillow.readthedocs.io/en/stable/releasenotes/12.2.0.html#prevent-fits-decompression-bomb"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "FITS GZIP decompression bomb in Pillow"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

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.