php-svg-lib possible DoS caused by infinite recursion when parsing SVG document

published 2023-12-12 2 y ago modified 2026-06-17 4 mo ago also GHSA-ff5x-7qg5-vwf2 , EUVD-2023-3195

cvss: 5.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.9%; EPSS 0.9% chance of exploitation in 30 days, percentile 59%
public exploits: 0; none known

php-svg-lib is an SVG file parsing / rendering library. Prior to version 0.5.1, when parsing the attributes passed to a `use` tag inside an svg document, an attacker can cause the system to go to an infinite recursion. Depending on the system configuration and attack pattern this could exhaust the memory available to the executing process and/or to the server itself. An attacker sending multiple request to a system to render the above payload can potentially cause resource exhaustion to the point that the system is unable to handle incoming request. Version 0.5.1 contains a patch for this issue.

Patch / fix

fixed in 2 distros 1 links 1

packagist phenx/php-svg-lib 0.5.1
dompdf php-svg-lib 0.5.1

php-dompdf-svg-lib Debian 12 0.5.0-3+deb12u1

debian advisories DEBIAN-CVE-2023-50251

github.com/dompdf/php-svg-lib@88163cb commit

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: partial
Assessed: 17 mo ago (2025-05-22)

Exploit prediction

0.88% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/dompdf/php-svg-lib/security/advisories/GHSA-ff5x-7qg5-vwf2 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
NVD	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	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected packages

ecosystem	package	affected	fixed in
packagist	phenx/php-svg-lib	<0.5.1	0.5.1

Affected products

dompdf php-svg-lib

Classification

Weakness

CWE-674 Uncontrolled Recursion

References

github.com /dompdf/php-svg-lib/commit/88163cbe562d9b391b3a352e54d9c89d02d77ee0
web, patch
github.com /dompdf/php-svg-lib/security/advisories/GHSA-ff5x-7qg5-vwf2
web, exploit, vendor-advisory
nvd.nist.gov /vuln/detail/CVE-2023-50251
advisory
github.com /dompdf/php-svg-lib
package

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.

Summary