CVE-2026-29063

CVE-2026-29063 affects Immutable.js, where prototype pollution is possible via mergeDeep(), mergeDeepWith(), merge(), Map.toJS(), and Map.toObject() APIs in versions prior to 3.8.3, 4.3.7, and 5.1.5. IBM security bulletins corroborate the issue and list affected IBM products (e.g., Cloud Pak for ...

CVE-2026-59879

Immutable.js List contains a 32-bit trie overflow in List.js setListBounds that, prior to versions 4.3.9 and 5.1.8, can mishandle an index or size in the 2^30–2^31 range, leading to an uncatchable infinite loop for empty Lists, unbounded allocation for populated Lists, or silent wrap of large set...

CVE-2026-59880

Immutable.js contains a HashCollision vulnerability in Map/Set keys prior to version 4.3.9 and 5.1.8: an adversary who controls inserted keys can craft many hash collisions in a HashCollisionNode, causing linear scans and CPU exhaustion during insertion and lookup. The issue is fixed in 4.3.9 and...