{"api_version":"1","generated_at":"2026-07-08T18:28:10+00:00","cve":"CVE-2026-59880","urls":{"html":"https://cve.report/CVE-2026-59880","api":"https://cve.report/api/cve/CVE-2026-59880.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-59880","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-59880"},"summary":{"title":"Immutable.js: Hash-collision algorithmic complexity denial of service in Immutable.Map/Set","description":"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.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-07-08 16:16:34","updated_at":"2026-07-08 17:17:26"},"problem_types":["CWE-407","CWE-407 CWE-407: Inefficient Algorithmic Complexity"],"metrics":[{"version":"4.0","source":"security-advisories@github.com","type":"Secondary","score":"8.7","severity":"HIGH","vector":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","data":{"version":"4.0","vectorString":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","baseScore":8.7,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}},{"version":"4.0","source":"CNA","type":"DECLARED","score":"8.7","severity":"HIGH","vector":"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","data":{"attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"NETWORK","baseScore":8.7,"baseSeverity":"HIGH","privilegesRequired":"NONE","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","vectorString":"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","version":"4.0","vulnAvailabilityImpact":"HIGH","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE"}}],"references":[{"url":"https://github.com/immutable-js/immutable-js/releases/tag/v5.1.8","name":"https://github.com/immutable-js/immutable-js/releases/tag/v5.1.8","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/immutable-js/immutable-js/security/advisories/GHSA-xvcm-6775-5m9r","name":"https://github.com/immutable-js/immutable-js/security/advisories/GHSA-xvcm-6775-5m9r","refsource":"134c704f-9b21-4f2e-91b3-4a467353bcc0","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/immutable-js/immutable-js/releases/tag/v4.3.9","name":"https://github.com/immutable-js/immutable-js/releases/tag/v4.3.9","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/immutable-js/immutable-js/commit/e51d49fc612ded5ec4dfb94ff294d22074269b0f","name":"https://github.com/immutable-js/immutable-js/commit/e51d49fc612ded5ec4dfb94ff294d22074269b0f","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/immutable-js/immutable-js/commit/3dd7e5655012597a41873e328bf9142a8901527b","name":"https://github.com/immutable-js/immutable-js/commit/3dd7e5655012597a41873e328bf9142a8901527b","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-59880","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-59880","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"immutable-js","product":"immutable-js","version":"affected < 4.3.9","platforms":[]},{"source":"CNA","vendor":"immutable-js","product":"immutable-js","version":"affected >= 5.0.0-beta.1, < 5.1.8","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"metrics":[{"other":{"content":{"id":"CVE-2026-59880","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","timestamp":"2026-07-08T16:13:29.483011Z","version":"2.0.3"},"type":"ssvc"}}],"providerMetadata":{"dateUpdated":"2026-07-08T16:13:46.106Z","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP"},"references":[{"tags":["exploit"],"url":"https://github.com/immutable-js/immutable-js/security/advisories/GHSA-xvcm-6775-5m9r"}],"title":"CISA ADP Vulnrichment"}],"cna":{"affected":[{"product":"immutable-js","vendor":"immutable-js","versions":[{"status":"affected","version":"< 4.3.9"},{"status":"affected","version":">= 5.0.0-beta.1, < 5.1.8"}]}],"descriptions":[{"lang":"en","value":"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."}],"metrics":[{"cvssV4_0":{"attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"NETWORK","baseScore":8.7,"baseSeverity":"HIGH","privilegesRequired":"NONE","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","vectorString":"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","version":"4.0","vulnAvailabilityImpact":"HIGH","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-407","description":"CWE-407: Inefficient Algorithmic Complexity","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-07-08T15:44:23.414Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"references":[{"name":"https://github.com/immutable-js/immutable-js/security/advisories/GHSA-xvcm-6775-5m9r","tags":["x_refsource_CONFIRM"],"url":"https://github.com/immutable-js/immutable-js/security/advisories/GHSA-xvcm-6775-5m9r"},{"name":"https://github.com/immutable-js/immutable-js/commit/3dd7e5655012597a41873e328bf9142a8901527b","tags":["x_refsource_MISC"],"url":"https://github.com/immutable-js/immutable-js/commit/3dd7e5655012597a41873e328bf9142a8901527b"},{"name":"https://github.com/immutable-js/immutable-js/commit/e51d49fc612ded5ec4dfb94ff294d22074269b0f","tags":["x_refsource_MISC"],"url":"https://github.com/immutable-js/immutable-js/commit/e51d49fc612ded5ec4dfb94ff294d22074269b0f"},{"name":"https://github.com/immutable-js/immutable-js/releases/tag/v4.3.9","tags":["x_refsource_MISC"],"url":"https://github.com/immutable-js/immutable-js/releases/tag/v4.3.9"},{"name":"https://github.com/immutable-js/immutable-js/releases/tag/v5.1.8","tags":["x_refsource_MISC"],"url":"https://github.com/immutable-js/immutable-js/releases/tag/v5.1.8"}],"source":{"advisory":"GHSA-xvcm-6775-5m9r","discovery":"UNKNOWN"},"title":"Immutable.js: Hash-collision algorithmic complexity denial of service in Immutable.Map/Set"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2026-59880","datePublished":"2026-07-08T15:44:23.414Z","dateReserved":"2026-07-07T16:40:07.982Z","dateUpdated":"2026-07-08T16:13:46.106Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-08 16:16:34","lastModifiedDate":"2026-07-08 17:17:26","problem_types":["CWE-407","CWE-407 CWE-407: Inefficient Algorithmic Complexity"],"metrics":{"cvssMetricV40":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"4.0","vectorString":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","baseScore":8.7,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-07-08T16:13:29.483011Z","id":"CVE-2026-59880","options":[{"exploitation":"poc"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"59880","Ordinal":"1","Title":"Immutable.js: Hash-collision algorithmic complexity denial of se","CVE":"CVE-2026-59880","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"59880","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"Immutable.js: Hash-collision algorithmic complexity denial of se"}]}}}