High
Immutable.js: Hash-collision algorithmic complexity denial of service in Immutable.Map/Set
Type: advisorySources: OSV
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-59880
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 4 Nov 2026, 20:10 UTC · Revision 1
Source evidence
Immutable.js: Hash-collision algorithmic complexity denial of service in Immutable.Map/Set
core-osv · Original sourcePublished 8 Jul 2026, 15:44 UTC
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.
osv:CVE-2026-59880
Complete source record
{
"id": "349ae6d74e3ee9b8b6630bb3f5485fc8eda072fbec7db21b1ed6954cce6f19e2",
"url": "https://osv.dev/vulnerability/CVE-2026-59880",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Immutable.js: Hash-collision algorithmic complexity denial of service in Immutable.Map/Set",
"summary": "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.",
"evidence": "osv:CVE-2026-59880",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2026-59880",
"aliases": [
"CVE-2026-59880",
"GHSA-xvcm-6775-5m9r"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "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"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/immutable-js/immutable-js",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "5da7919616a015cc03173f8f0bd3ee7101ab27f2"
},
{
"introduced": "c90cdc263d94553b2439bbff4f761f4df7f361af"
},
{
"fixed": "6496539bd1e9dfa75ce11b053e7d70d79e9ac6f7"
},
{
"fixed": "3dd7e5655012597a41873e328bf9142a8901527b"
},
{
"fixed": "e51d49fc612ded5ec4dfb94ff294d22074269b0f"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:immutable-js:immutable:*:*:*:*:*:node.js:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "4.3.9"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:immutable-js:immutable:*:*:*:*:*:node.js:*:*",
"range": [
{
"introduced": "5.0.0"
},
{
"fixed": "5.1.8"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "3dd7e5655012597a41873e328bf9142a8901527b"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "e51d49fc612ded5ec4dfb94ff294d22074269b0f"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "5da7919616a015cc03173f8f0bd3ee7101ab27f2"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v4.3.9"
},
{
"range": [
{
"fixed": "6496539bd1e9dfa75ce11b053e7d70d79e9ac6f7"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v5.1.8"
}
]
}
}
],
"versions": [
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"v5.1.6",
"v4.3.8",
"v5.1.5",
"v4.3.7",
"v5.1.4",
"v5.1.3",
"v5.1.2",
"v5.1.1",
"v5.0.2",
"v5.0.1",
"v4.3.6",
"v4.3.5",
"v4.3.4",
"v4.3.3",
"v4.3.1",
"v4.3.0",
"v4.2.2",
"v4.2.1",
"v4.2.0",
"v4.0.0",
"v4.0.0-rc.15",
"v4.0.0-rc.14",
"v4.0.0-rc.13",
"v4.0.0-rc.12",
"v4.0.0-rc.11",
"v4.0.0-rc.10",
"v4.0.0-rc.9",
"v4.0.0-rc.8",
"v4.0.0-rc.7",
"v4.0.0-rc.6",
"v4.0.0-rc.4",
"v3.8.1",
"v4.0.0-rc.3",
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"v3.8.0",
"3.7.6",
"3.7.5",
"3.7.4",
"3.7.3",
"3.7.2",
"3.7.1",
"3.7.0",
"3.6.4",
"3.6.3",
"3.6.2",
"3.6.1",
"3.6.0",
"3.5.0",
"3.4.1",
"3.4.0",
"3.3.0",
"3.2.1",
"3.2.0",
"3.1.0",
"3.0.3",
"3.0.2",
"3.0.1",
"3.0.0",
"2.6.2",
"2.6.1",
"2.6.0",
"2.5.1",
"2.5.0",
"2.3.2",
"2.3.1",
"2.3.0",
"2.2.2",
"2.2.1",
"2.2.0",
"2.1.0",
"2.0.17",
"2.0.16",
"2.0.15",
"2.0.14",
"2.0.13",
"2.0.12",
"2.0.11",
"2.0.10",
"2.0.9",
"2.0.8",
"2.0.7",
"2.0.6",
"2.0.5",
"2.0.4"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-59880.json"
}
}
],
"modified": "2026-10-28T02:30:39.065758942Z",
"provider": "osv",
"references": [
"https://github.com/immutable-js/immutable-js/releases/tag/v4.3.9",
"https://github.com/immutable-js/immutable-js/releases/tag/v5.1.8",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59880.json",
"https://github.com/immutable-js/immutable-js/security/advisories/GHSA-xvcm-6775-5m9r",
"https://nvd.nist.gov/vuln/detail/CVE-2026-59880",
"https://github.com/immutable-js/immutable-js/commit/3dd7e5655012597a41873e328bf9142a8901527b",
"https://github.com/immutable-js/immutable-js/commit/e51d49fc612ded5ec4dfb94ff294d22074269b0f"
],
"provider_metadata": {
"cwe_ids": [
"CWE-407"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59880.json"
}
},
"related_cves": [
{
"value": "CVE-2026-59880",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 506525,
"published_at": "2026-07-08T15:44:23.414+00:00"
}