Vulnerability · Published Mar 13, 2026 · Assigned by GitHub_M
CVE-2026-31899CairoSVG vulnerable to Exponential DoS via recursive <use> element amplification
High 7.5
In plain English
A high-severity security flaw in CairoSVG from Kozea. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.5%top 55.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack tooling1Public PoC
Official description
CairoSVG is an SVG converter based on Cairo, a 2D graphics library. Prior to Kozea/CairoSVG has exponential denial of service via recursive <use> element amplification in cairosvg/defs.py. This causes CPU exhaustion from a small input.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | py3-cairosvg | 2.9.0-r0 | ALPINE-CVE-2026-31899 |
| Alpine:v3.24 | py3-cairosvg | 2.9.0-r0 | ALPINE-CVE-2026-31899 |
| Debian:12 | cairosvg | no fix listed | DEBIAN-CVE-2026-31899 |
| Debian:13 | cairosvg | no fix listed | DEBIAN-CVE-2026-31899 |
| Debian:14 | cairosvg | 2.9.0-1 | DEBIAN-CVE-2026-31899 |
| PyPI | cairosvg | 2.9.0 | PYSEC-2026-2122 |
| PyPI | cairosvg | 2.9.0 | GHSA-f38f-5xpm-9r7c |
| Ubuntu:22.04:LTS | cairosvg | no fix listed | UBUNTU-CVE-2026-31899 |
| Ubuntu:24.04:LTS | cairosvg | no fix listed | UBUNTU-CVE-2026-31899 |
| Ubuntu:25.10 | cairosvg | no fix listed | UBUNTU-CVE-2026-31899 |
| Ubuntu:26.04:LTS | cairosvg | no fix listed | UBUNTU-CVE-2026-31899 |
| Ubuntu:26.10 | cairosvg | no fix listed | UBUNTU-CVE-2026-31899 |
Affected products (as reported)
Weakness: CWE-674 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H