Pillow vulnerability can cause write buffer overflow on BCn encoding
There is a heap buffer overflow when writing a sufficiently large (>64k encoded with default settings) image in the DDS format due to writing into a buffer without checking for available space. This only affects users who save untrusted data as a compressed DDS image. * Unclear how large the potential write could be. It is likely limited by process segfault, so it's not necessarily deterministic. It may be practically unbounded. * Unclear if there's a restriction on the bytes that could be emitted. It's likely that the only restriction is that the bytes would be emitted in chunks of 8 or 16. This was introduced in Pillow 11.2.0 when the feature was added.
describes (1)
Related CVEs.
| ID | severity | exploitable | ||
|---|---|---|---|---|
| CVE-2025-48379US | medium5.5 | — | ||
Pillow is a Python imaging library. In versions 11.2.0 to before 11.3.0, there is a heap buffer overflow when writing a sufficiently large (>64k encoded with default settings) imag… | ||||
references
External citations — patches, advisories, analysis.
- https://github.com/pypa/advisory-database/tree/main/vulns/pillow/PYSEC-2025-61.yamlWEB
- https://github.com/python-pillow/PillowPACKAGE
- https://github.com/python-pillow/Pillow/commit/ef98b3510e3e4f14b547762764813d7e5ca3c5a4WEB
- https://github.com/python-pillow/Pillow/pull/9041WEB
- https://github.com/python-pillow/Pillow/releases/tag/11.3.0WEB
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-xg8h-j46f-w952WEB
- https://nvd.nist.gov/vuln/detail/CVE-2025-48379ADVISORY
Advisories like this name the exposed products attackers go after on your perimeter. See what is exposed on your perimeter with a free passive scan.
Free scan