CVE-2026-112894 — Pillow: Quadratic-time DoS in PDF save_all (PdfParser.next_object_id)
Pillow is a Python imaging library. From 5.1.0 until 13.0.0, Pillow takes quadratic time to reserve PDF object identifiers when saving many frames with save_all enabled. PdfPars…
Published: 2026-10-19 · CVSS: 8.7 · CVSS 4.0
Pillow is a Python imaging library. From 5.1.0 until 13.0.0, Pillow takes quadratic time to reserve PDF object identifiers when saving many frames with save_all enabled. PdfParser.next_object_id() repeatedly rebuilds and scans all previously reserved identifiers for every object. An attacker can supply a multi-frame image, including a small APNG with a large declared frame count, to an application that converts it to a multipage PDF. This can consume excessive CPU and deny service. This issue is fixed in version 13.0.0.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7