Algorithmic Complexity Denial of Service in svg-sanitizer by Daryll Doyle
CVE-2026-121444

8.7HIGH

Key Information:

Vendor

Darylldoyle

Status
Svg-sanitizer
Vendor
CVE Published:
3 November 2026

What is CVE-2026-121444?

The svg-sanitizer, specifically versions 0.11.0 and earlier, has a vulnerability allowing attackers to exploit the hasInfiniteLoop() and countUse() functions. By uploading a carefully crafted SVG with multiple layers (up to 15 levels deep) of usage references, an attacker can induce excessive path enumeration that can overwhelm PHP workers and severely disrupt service availability. This vulnerability highlights the need for improved handling of complex SVG structures to mitigate potential denial of service attacks.

Affected Version(s)

svg-sanitizer 0.11.0 < 1.1.0

svg-sanitizer 1.1.0

References

https://github.com/darylldoyle/svg-sanitizer/security/adv...
vendor-advisory
https://www.vulncheck.com/advisories/svg-sanitizer-0.11.0...
third-party-advisory

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

ba-am
AlpetGexha
.