Inefficient Algorithmic Complexity
CVE-2026-59880
Summary
Immutable.js provides many Persistent Immutable data structures. Prior to 4.3.9 and 5.x prior to 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.
- LOW
- NETWORK
- NONE
- UNCHANGED
- NONE
- NONE
- NONE
- HIGH
CWE-407 - Inefficient Algorithmic Complexity
An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.
References
Advisory Timeline
- Published