CVE-2026-112399 — Pillow: APNG background disposal allocates full canvas before decompression bomb check
Pillow is a Python imaging library. From 8.1.0 until 13.0.0, Pillow can allocate an APNG disposal background at the full canvas size before applying the decompression-bomb check…
Published: 2026-10-19 · CVSS: 8.7 · CVSS 4.0
Pillow is a Python imaging library. From 8.1.0 until 13.0.0, Pillow can allocate an APNG disposal background at the full canvas size before applying the decompression-bomb check. A crafted APNG with a small first frame, a very large declared canvas, and background disposal or first-frame OP_PREVIOUS reaches PngImageFile._seek while Image.open() positions frame zero. The full-canvas allocation occurs inside Image.open() without requiring pixel loading or frame iteration. This can exhaust memory and deny service. This issue is fixed in version 13.0.0.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7