CVE-2026-121443 json
svg-sanitizer from 1.1.0 before 1.1.1 Denial of Service via Unclosed Tag
published 6d ago modified 11h ago also EUVD-2026-115865
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 22%
- public exploits
- 0
- none known
Summary
svg-sanitizer from 1.1.0 before 1.1.1 contains a denial of service vulnerability that allows remote attackers to crash requests by submitting SVG input ending inside an unclosed tag. Attackers can upload truncated input like a single '<' to trigger an uncaught ValueError from strpos() in hasElementWithTooManyAttributes() or hasInternalDtdSubset() on PHP 8, failing the request.
Patch / fix
- darylldoyle svg-sanitizer 1.1.1
Is CVE-2026-121443 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 11h ago
Exploit prediction
0.30% chance of exploitation in the next 30 days, higher than 22% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- github.com https://github.com/darylldoyle/svg-sanitizer/security/advisories/GHSA-f7cw-vfxq-7ph2 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| CNA | 4.0 | 6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- darylldoyle svg-sanitizer
Classification
- Weakness
-
- CWE-248 Uncaught Exception
References
-
github.com
/darylldoyle/svg-sanitizer/security/advisories/GHSA-f7cw-vfxq-7ph2
vendor-advisory, exploit
-
vulncheck.com
/advisories/svg-sanitizer-from-1.1.0-before-1.1.1-denial-of-service-via-unclosed-tag
third-party-advisory
Sources
- CVE List CVE-2026-121443
- NVD CVE-2026-121443
Fencer Intel 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.