Bug 2511491

Summary: CVE-2026-59880 mozjs78: Immutable.js: Denial of Service via crafted hash collisions in Map and Set [epel-all]
Product: [Fedora] Fedora EPEL Reporter: Vipul Nair <vinair>
Component: mozjs78Assignee: František Zatloukal <fzatlouk>
Status: CLOSED WONTFIX QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: epel10CC: epel-packagers-sig, fzatlouk, kalevlember
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["e4402ad6-b625-48c6-980d-aef247500fa9"]}
Fixed In Version: Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-10-06 08:09:43 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2498124    

Description Vipul Nair 2026-08-05 12:48:38 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.

Immutable.js provides many Persistent Immutable data structures. Prior to 4.3.9 and 5.1.8, Immutable.Map and Immutable.Set keep keys that share the same 32-bit hash in a HashCollisionNode collision bucket that is scanned linearly, allowing an attacker who controls keys inserted into a Map, such as through Immutable.Map(obj), Immutable.fromJS(obj), state.merge(userObject), or mergeDeep, to craft many colliding keys and degrade insertion and lookup to consume disproportionate CPU. This issue is fixed in versions 4.3.9 and 5.1.8.
Comment 1 František Zatloukal 2026-10-06 08:09:43 UTC 
Closing CVE bug as not relevant to the mozjs package, and there is sadly no option to opt out from these reports :( .