Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Pillow versions from 8.2.0 before 12.3.0 are affected. A crafted tiled JPEG2000 image can make the decoder grow its buffer across tiles, using much more transient memory than the image should need and possibly causing out-of-memory failures. An attacker only needs to get Pillow to open and load the file, such as through an image upload. Upgrade to Pillow 12.3.0 or later. The source lists no other workaround.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 8.7 | High | 4.0 | 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 | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0039, the 33rd percentile, on 15 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 7 Jul 2026, 08:58 UTC Published by the maintainers as a GitHub repository advisory
- 31 Oct 2026, 14:29 UTC First seen by agentprime
- 31 Oct 2026, 14:29 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-vjc4-5qp5-m44j
- OSV: GHSA-vjc4-5qp5-m44j
- github.com/python-pillow/Pillow/security/advisories/GHSA-vjc4-5qp5-m44j
- nvd.nist.gov/vuln/detail/CVE-2026-59204
- github.com/python-pillow/Pillow/pull/9704
- github.com/python-pillow/Pillow/commit/13ada41172142f2fd9f0906f615a00ea623a11ca
- github.com/python-pillow/Pillow
- github.com/python-pillow/Pillow/releases/tag/12.3.0