GHSA-fc9g-5qg7-mf45

Suggest an improvement
Source
https://github.com/advisories/GHSA-fc9g-5qg7-mf45
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-fc9g-5qg7-mf45/GHSA-fc9g-5qg7-mf45.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-fc9g-5qg7-mf45
Aliases
Published
2026-10-21T20:38:43Z
Modified
2026-10-21T20:45:04Z
Severity
  • 6.9 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N CVSS Calculator
Summary
Pillow: Quadratic GIF comment copying during save
Details

On Pillow 12.3.0 and upstream main (ad277e2761b489681e71b51e91367d46b0ceabb9), a GIF with a long comment makes _get_global_header() copy portions of the comment repeatedly when saving, including comments carried over from untrusted images. I suggest provisional Moderate severity for crafted-image CPU denial of service, with CVSS-B 6.9 assuming a network service automatically opens unauthenticated uploads and they are resaved as GIFs; impact depends on input-size, concurrency, and worker CPU limits.

Database specific 
{
    "cwe_ids":  [
        "CWE-407"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-10-21T20:38:43Z",
    "nvd_published_at":  "2026-10-19T22:17:08Z",
    "severity":  "MODERATE"
}
References

Affected packages

PyPI / pillow

Package

Name
pillow
View open source insights on deps.dev
Purl
pkg:pypi/pillow

Affected ranges

Type
ECOSYSTEM
Events
Introduced
9.2.0
Fixed
13.0.0

Affected versions

9.*
9.2.0
9.3.0
9.4.0
9.5.0
10.*
10.0.0
10.0.1
10.1.0
10.2.0
10.3.0
10.4.0
11.*
11.0.0
11.1.0
11.2.1
11.3.0
12.*
12.0.0
12.1.0
12.1.1
12.2.0
12.3.0

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-fc9g-5qg7-mf45/GHSA-fc9g-5qg7-mf45.json"