High 8.7Published Jul 8, 2026

CVE-2026-59879Immutable.js `List` 32-bit trie overflow → unrecoverable DoS

Updated under an hour ago (Oct 26, 2026, 4:40 PM ET)

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Every CVE for immutable-js

Exploited in the last 30 days

Immutable.js provides many Persistent Immutable data structures. Prior to 4.3.9 and 5.1.8, List#set, List#setSize, List#setIn, List#updateIn, and the functional set, setIn, and updateIn mishandle an index or size in the range 2 ** 30 to 2 ** 31 in setListBounds in src/List.js, causing an empty List to enter an uncatchable infinite loop, a populated List to allocate without bound until process abort, or setSize to silently wrap large values. This issue is fixed in versions 4.3.9 and 5.1.8.

CVSS: 8.7 HIGH (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness (CWE): CWE-190, CWE-400, CWE-835, CWE-1284
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Jul 8, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

immutable-js immutable-js immutable_js:immutable_js (from the name)	from 5.0.0-beta.1, < 5.1.8; before 4.3.9	CNA record
immutable-js immutable immutable-js:immutable	before 4.3.9; from 5.0.0 before 5.1.8	NVD

References

References

https://github.com/immutable-js/immutable-js/security/advisories/GHSA-v56q-mh7h-f735	x-refsource-confirm, exploit, mitigation, vendor-advisory
https://github.com/immutable-js/immutable-js/commit/a1a1ee412dcaa380ab325196283d06594ffe4b84	x-refsource-misc, patch
https://github.com/immutable-js/immutable-js/commit/f0bc997d8eb9886aff2236635aa210a95a04304a	x-refsource-misc, patch
https://github.com/immutable-js/immutable-js/releases/tag/v4.3.9	x-refsource-misc, product, release-notes
https://github.com/immutable-js/immutable-js/releases/tag/v5.1.8	x-refsource-misc, product, release-notes

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.