Vulnerability · Published May 9, 2026 · Assigned by GitHub_M
CVE-2026-42308Pillow: Integer overflow when processing fonts
Medium 5.1
In plain English
A medium-severity integer overflow in Pillow from python-pillow. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 1% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 4.0)5.1Medium
Exploit odds (30 days)0.1%top 98.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Pillow is a Python imaging library. Prior to version 12.2.0, if a font advances for each glyph by an exceeding large amount, when Pillow keeps track of the current position, it may lead to an integer overflow. This issue has been patched in version 12.2.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | pillow | no fix listed | DEBIAN-CVE-2026-42308 |
| Debian:13 | pillow | 11.1.0-5+deb13u3 | DEBIAN-CVE-2026-42308 |
| Debian:14 | pillow | 12.2.0-1 | DEBIAN-CVE-2026-42308 |
| PyPI | pillow | 12.2.0 | PYSEC-2026-165 |
| PyPI | pillow | 12.2.0 | GHSA-wjx4-4jcj-g98j |
| Ubuntu:22.04:LTS | pillow | 9.0.1-1ubuntu0.4 | USN-8399-1 |
| Ubuntu:22.04:LTS | pillow | 9.0.1-1ubuntu0.4 | UBUNTU-CVE-2026-42308 |
| Ubuntu:24.04:LTS | pillow | 10.2.0-1ubuntu1.2 | USN-8399-1 |
| Ubuntu:24.04:LTS | pillow | 10.2.0-1ubuntu1.2 | UBUNTU-CVE-2026-42308 |
| Ubuntu:25.10 | pillow | 11.3.0-1ubuntu1.3 | USN-8399-1 |
| Ubuntu:25.10 | pillow | 11.3.0-1ubuntu1.3 | UBUNTU-CVE-2026-42308 |
| Ubuntu:26.04:LTS | pillow | 12.1.1-2ubuntu1.2 | UBUNTU-CVE-2026-42308 |
| Ubuntu:26.04:LTS | pillow | 12.1.1-2ubuntu1.2 | USN-8399-1 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| python-pillow | Pillow | < 12.2.0 |
Weakness: CWE-190 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
References
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-wjx4-4jcj-g98j x_refsource_CONFIRM
- https://github.com/python-pillow/Pillow/releases/tag/12.2.0 x_refsource_MISC