CVE-2026-65911

Aliases:UBUNTU-CVE-2026-65911DEBIAN-CVE-2026-65911
Advisory lineage Upstream: 0 Downstream: 2
Analyzed
Published: 23 Jul 2026, 13:16
Last modified:27 Jul 2026, 16:20

Vulnerability Summary

Overall Risk (default)
medium
34/100
CVSS Score
6.1 MEDIUM
v3.1 (cve.org)
EPSS Score
0.23% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
1 found
Dark Web
Not detected

Timeline

23 Jul 2026, 13:16
Published
Vulnerability first disclosed
27 Jul 2026, 16:20
Last Modified
Vulnerability information updated

Description

In DOMPurify through 3.3.3, function predicates supplied via ADD_ATTR or ADD_TAGS to DOMPurify.sanitize() persist in internal state (EXTRA_ELEMENT_HANDLING) across subsequent sanitize() calls on the same instance. If a later call on the same instance provides ADD_ATTR or ADD_TAGS as an array rather than a function, the previously set function handler is neither cleared nor overwritten, so it continues to approve attacker-controlled attributes or tags. This can allow dangerous event-handler attributes or forbidden tags (bypassing FORBID_TAGS) to survive sanitization, resulting in cross-site scripting. The vendor (Cure53) considers this an edge case outside DOMPurify's threat model; the referenced advisory lists 3.4.0 as the patched version.

CVSS Metrics

  • v4.0•MEDIUM•Score: 5.1CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
  • v4.0•MEDIUM•Score: 5.1CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/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
  • v3.1•MEDIUM•Score: 6.1CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS Trends

Current EPSS score: 0.23%• Percentile: 14%

Techniques & Countermeasures

  • CWE-79•Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

    The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

Affected Systems

  • cure53•dompurify

    < 3.4.0

  • debian•node-dompurify

    all | all | < 3.4.1+dfsg-1

  • ubuntu•node-dompurify

    all | all | all

References (5)