CVE-2025-48379

HIGH7.1EPSS 0.10%

Pillow vulnerability can cause write buffer overflow on BCn encoding

Published: 7/1/2025Modified: 2/4/2026

Description

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.

Affected packages (3)

  • Bitnami/pillow>= 11.2.0
  • PyPI/pillow>= 11.2.0, < 11.3.0
  • PyPI/pillowfrom 0, < 89f1f4626a2aaf5f3d5ca6437f41def2998fbe09, < ef98b3510e3e4f14b547762764813d7e5ca3c5a4 | >= 11.2.0, < 11.3.0

CVSS scores

SourceVersionSeverityVector
osvCVSS 3.1HIGH7.1CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

References (7)