CVE-2026-65902
DOMPurify before 3.4.7 (affected versions <= 3.4.5) passes direct references to the module-level DEFAULT_ALLOWED_TAGS and DEFAULT_ALLOWED_ATTR sets to the uponSanitizeElement and uponSanitizeAttribute hooks via data.allowedTags / data.allowedAttributes when sanitize is called without an explicit cfg.ALLOWED_TAGS / cfg.ALLOWED_ATTR array. A hook that mutates these fields permanently widens the default allow-lists for the lifetime of the DOMPurify instance, so all subsequent default-config sanitize calls inherit the widened defaults and attacker payloads using the poisoned tag/attribute name survive sanitization. removeAllHooks(), clearConfig(), and passing a fresh cfg do not recover the state; only constructing a new DOMPurify instance does.
- CVSS 4.0
- 5.3
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N - CVSS 3.1
- 6.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 28% of CVEs (scores of 2026-10-25)
- CWE
- CWE-501
- Published
- Modified
- Record from
- the NVD, synced
Affected
- cure53:dompurify
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-76mc-f452-cxcm | npm | dompurify | <3.4.7 | 3.4.7 |
References
- https://github.com/cure53/DOMPurify/commit/7996f1dc78eb8b7922388aed75d94a9f8fad9a36
- https://github.com/cure53/DOMPurify/security/advisories/GHSA-76mc-f452-cxcm
- https://www.vulncheck.com/advisories/dompurify-before-hook-mutation-pollution-via-allowedtags
- https://github.com/cure53/DOMPurify/security/advisories/GHSA-76mc-f452-cxcm