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Fencer Vulns
high 7.5

CVE-2026-31899 json

CairoSVG vulnerable to Exponential DoS via recursive <use> element amplification

published 2026-03-13 7 mo ago modified 2026-07-13 3 mo ago also EUVD-2026-12091 , GHSA-f38f-5xpm-9r7c , PYSEC-2026-2122

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 46%
public exploits
0
none known

Summary

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.

Patch / fix

  • pypi cairosvg 2.9.0
  • courtbouillon cairosvg 2.9.0
  • cairosvg Debian 14 2.9.0-1

debian advisories DEBIAN-CVE-2026-31899

  • python-CairoSVG SLES for SAP applications 16.0, SLES 16.0 2.7.1-160000.3.1
  • python-CairoSVG SLE Module for Python 3 15 SP7, openSUSE Leap 15.6 2.7.1-150400.9.6.1

suse advisories SUSE-SU-2026:22024-1SUSE-SU-2026:1421-1

  • ansible-creator openSUSE Tumbleweed 26.8.0-1.1
  • python-CairoSVG openSUSE Tumbleweed 2.9.0-1.1

opensuse advisories openSUSE-SU-2026:11729-1openSUSE-SU-2026:10379-1

  • py3-cairosvg Alpine 3.24, Alpine 3.23 2.9.0-r0

alpine advisories ALPINE-CVE-2026-31899

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-31899 updated cvss 7.5

CairoSVG: CairoSVG: Denial of Service via recursive <use> element amplification

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
7 mo ago

Exploit prediction

0.56% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/Kozea/CairoSVG/security/advisories/GHSA-f38f-5xpm-9r7c referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
OSV 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
pypi cairosvg
<2.9.0
2.9.0

Affected products

  • Kozea CairoSVG

Classification

Weakness
  • CWE-674 Uncontrolled Recursion
  • CWE-400 Uncontrolled Resource Consumption

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.