CVE-2026-65902
Last modified
CVE-2026-65902 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. 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. EPSS estimates a 0.19% chance of exploitation in the next 30 days.
Description
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
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/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
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Cure53 | Dompurify | < 3.4.7 |
References
- https://github.com/cure53/DOMPurify/security/advisories/GHSA-76mc-f452-cxcmExploit, Third Party Advisory
- https://github.com/cure53/DOMPurify/security/advisories/GHSA-76mc-f452-cxcmExploit, Third Party Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-65902?
How severe is CVE-2026-65902?
How do I fix CVE-2026-65902?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-65897Grav API Plugin versions before 1.0.10 fail to validate the …8.8
- CVE-2026-65898DOMPurify before 3.4.11 fails to clone the ALLOWED_ATTR allo…7.2
- CVE-2026-65899DOMPurify 3.0.0 before 3.4.9 does not reset the retained Tru…6.1
- CVE-2026-6590A vulnerability was detected in ComfyUI up to 0.13.0. This i…4.3
- CVE-2026-65900DOMPurify versions >=3.0.0 and before 3.4.8, when configured…6.1
- CVE-2026-65901DOMPurify through 3.4.6 contains a cross-site scripting vuln…6.1
- CVE-2026-65903DOMPurify before 3.4.0 contains a logic error in the ADD_TAG…6.1
- CVE-2026-65904DOMPurify through 3.3.3 fails to sanitize DOM elements passe…4.7
- CVE-2026-65906In JetBrains TeamCity before 2026.1.2, 2025.11.6 сode execut…10
- CVE-2026-65907In JetBrains TeamCity before 2026.1.2, 2025.11.6 code execut…9.1
- CVE-2026-65908In JetBrains PyCharm before 2026.1.4, 2026.2 arbitrary code …8.6
- CVE-2026-6591A flaw has been found in ComfyUI up to 0.13.0. Affected is t…4.3
Are you affected by CVE-2026-65902?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST
