PYSEC-2026-4204 CairoSVG: Quadratic-time DoS parsing a crafted SVG <path>

Summary Rendering an untrusted SVG whose contains many segments is On² CPU. A single under 1 MiB burns tens of seconds. Two independent On² sites in cairosvg/path.py: 1. Tokenizer — the path-data parser consumes the d string with a while string: loop that repeatedly slices/re-scans the remaining...

CairoSVG: Quadratic-time DoS parsing a crafted SVG <path>

Rendering an untrusted SVG whose contains many segments is On² CPU. A single under 1 MiB burns tens of seconds. Two independent On² sites in cairosvg/path.py: 1. Tokenizer — the path-data parser consumes the d string with a while string: loop that repeatedly slices/re-scans the remaining string...