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

[ Why it matters ]Priority signals

• Public proof-of-concept exploit exists (CISA SSVC)

[ Description ]Official description

CairoSVG is an SVG converter based on Cairo, a 2D graphics library. Prior to 2.9.1, rendering an attacker-controlled SVG with a path containing many segments can cause quadratic CPU consumption in cairosvg/path.py. The path tokenizer repeatedly slices and rescans the remaining path data, while draw_markers drains node.vertices with node.vertices.pop(0), causing repeated linear-time work. The svg2png, svg2pdf, and svg2ps APIs reach these operations during ordinary rendering, allowing a sub-megabyte SVG to consume substantial CPU and deny service to a rendering application. This issue is fixed in version 2.9.1.

[ Fixes ]Fixes and patches

• cairosvg 2.9.1Fixed version · GitHub Advisories · pip package cairosvg: upgrade to 2.9.1 or later (affected <= 2.9.0)

[ Packages ]Affected open-source packages

• cairosvg pipAffected <= 2.9.0 · fixed in 2.9.1 · GHSA-c3jg-qh8m-j3h2

[ References ]References

• github.com/Kozea/CairoSVG/commit/9d63f049f9988d0ddda3eb94564ac3a50a286523
• github.com/Kozea/CairoSVG/commit/a4d585eb374724b79676e9cceaa9e9a1a4358565
• github.com/Kozea/CairoSVG/releases/tag/2.9.1
• github.com/Kozea/CairoSVG/security/advisories/GHSA-c3jg-qh8m-j3h2