High 7.5Published Jul 8, 2026

CVE-2026-59880Immutable.js provides many Persistent Immutable data structures.

Updated under an hour ago (2026-10-19 07:00 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for immutable-js immutable

Exploited in the last 30 days

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.

CVSS: 7.5 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-407
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Analyzed
Record last updated: Jul 10, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

immutable-js immutable immutable-js:immutable	before 4.3.9; from 5.0.0 before 5.1.8	NVD

References

https://github.com/immutable-js/immutable-js/commit/3dd7e5655012597a41873e328bf9142a8901527bpatch
https://github.com/immutable-js/immutable-js/commit/e51d49fc612ded5ec4dfb94ff294d22074269b0fpatch
https://github.com/immutable-js/immutable-js/releases/tag/v4.3.9release-notes
https://github.com/immutable-js/immutable-js/releases/tag/v5.1.8release-notes
https://github.com/immutable-js/immutable-js/security/advisories/GHSA-xvcm-6775-5m9rexploit, mitigation, vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.