CVE-2026-59880: Immutable.js: Hash-collision algorithmic complexity denial of service in Immutable.Map/Set
Description
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.
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H · CWE-407
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
immutable-js: immutable-js
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- github.com/immutable-js/immutable-js/commit/3dd7e5655012597a41873e328bf9142a8901… (opens in new tab)
- github.com/immutable-js/immutable-js/commit/e51d49fc612ded5ec4dfb94ff294d2207426… (opens in new tab)
- github.com/immutable-js/immutable-js/releases/tag/v4.3.9 (opens in new tab)
- github.com/immutable-js/immutable-js/releases/tag/v5.1.8 (opens in new tab)
- github.com/immutable-js/immutable-js/security/advisories/GHSA-xvcm-6775-5m9r (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)