Bug 2520399

Summary: CVE-2026-65914 nextcloud: DOMPurify: Cross-Site Scripting vulnerability allows arbitrary code execution [epel-all]
Product: [Fedora] Fedora EPEL Reporter: Ganesh <gnaik>
Component: nextcloudAssignee: Andrew Bauer <zonexpertconsulting>
Status: CLOSED CURRENTRELEASE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: epel10CC: pampelmuse, zonexpertconsulting
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["8dae98f5-fd70-458e-839a-e2b403cd1fef"]}
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Last Closed: 2026-08-20 16:37:58 UTC Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On:    
Bug Blocks: 2506430    

Description Ganesh 2026-08-20 15:56:54 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

DOMPurify before 3.3.2 contains a mutation-XSS vulnerability when sanitized HTML is reinserted into special parsing contexts using innerHTML with wrappers like script, xmp, iframe, noembed, noframes, or noscript. Attackers can craft payloads with closing sequences that break out of the wrapper context during reparsing, reactivating dangerous markup with event handlers to execute JavaScript.
Comment 1 Andrew Bauer 2026-08-20 16:37:58 UTC 
This bug is not valid. As of this writing, the current Nextcloud 34.0.3 release contain DOMPurify 3.4.13 which does not contain this CVE.

See:
https://github.com/nextcloud/server/blob/v34.0.3/package-lock.json#L6512