Quick answers
- Is CVE-2026-121443 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-121443 being exploited in the wild.
- How severe is CVE-2026-121443?
- Medium severity, with a CVSS score of 5.3, published 3 November 2026.
- Which products and versions are affected?
- Enshrined Svg-Sanitizer 1.1.0.
- Is there a fix for CVE-2026-121443?
- Yes: fixed in 1.1.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-121443 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-121443?
- Check whether you run Enshrined Svg-Sanitizer at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: 1.1.1
Technical details
The vulnerability is an uncaught ValueError on PHP 8 in the strpos() function within hasElementWithTooManyAttributes() and hasInternalDtdSubset() methods when the input ends inside an unclosed tag. The methods do not validate that the offset parameter stays within string bounds before calling strpos(), causing a crash instead of returning false. The issue affects version 1.1.0 but was fixed in 1.1.1 by adding bounds checks before the problematic function calls.
Affected products
- enshrined svg-sanitizer 1.1.0
Timeline
- 2026-10-20: disclosed
- 2026-11-03: advisory