{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-66456", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2025-12-01T22:51:54.580Z", "datePublished": "2025-12-09T19:43:10.252Z", "dateUpdated": "2025-12-09T20:35:44.683Z"}, "containers": {"cna": {"title": "Elysia vulnerable to prototype pollution with multiple standalone schema validation", "problemTypes": [{"descriptions": [{"cweId": "CWE-1321", "lang": "en", "description": "CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')", "type": "CWE"}]}], "metrics": [{"cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 9.1, "baseSeverity": "CRITICAL", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N", "version": "4.0"}}], "references": [{"name": "https://github.com/elysiajs/elysia/security/advisories/GHSA-hxj9-33pp-j2cc", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-hxj9-33pp-j2cc"}, {"name": "https://github.com/elysiajs/elysia/security/advisories/GHSA-8vch-m3f4-q8jf", "tags": ["x_refsource_MISC"], "url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-8vch-m3f4-q8jf"}, {"name": "https://github.com/elysiajs/elysia/pull/1564", "tags": ["x_refsource_MISC"], "url": "https://github.com/elysiajs/elysia/pull/1564"}, {"name": "https://github.com/elysiajs/elysia/commit/26935bf76ebc43b4a43d48b173fc853de43bb51e", "tags": ["x_refsource_MISC"], "url": "https://github.com/elysiajs/elysia/commit/26935bf76ebc43b4a43d48b173fc853de43bb51e"}, {"name": "https://github.com/elysiajs/elysia/commit/3af978663e437dccc6c1a2a3aff4b74e1574849e", "tags": ["x_refsource_MISC"], "url": "https://github.com/elysiajs/elysia/commit/3af978663e437dccc6c1a2a3aff4b74e1574849e"}], "affected": [{"vendor": "elysiajs", "product": "elysia", "versions": [{"version": ">= 1.4.0, < 1.4.17", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2025-12-09T19:43:10.252Z"}, "descriptions": [{"lang": "en", "value": "Elysia is a Typescript framework for request validation, type inference, OpenAPI documentation and client-server communication. Versions 1.4.0 through 1.4.16 contain a prototype pollution vulnerability in `mergeDeep` after merging results of two standard schema validations with the same key. Due to the ordering of merging, there must be an any type that is set as a standalone guard, to allow for the `__proto__ prop` to be merged. When combined with GHSA-8vch-m3f4-q8jf this allows for a full RCE by an attacker. This issue is fixed in version 1.4.17. To workaround, remove the `__proto__ key` from body."}], "source": {"advisory": "GHSA-hxj9-33pp-j2cc", "discovery": "UNKNOWN"}}, "adp": [{"references": [{"url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-hxj9-33pp-j2cc", "tags": ["exploit"]}, {"url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-8vch-m3f4-q8jf", "tags": ["exploit"]}], "metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2025-12-09T20:11:35.267669Z", "id": "CVE-2025-66456", "options": [{"Exploitation": "poc"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2025-12-09T20:35:44.683Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2025-66456", "role": "CISA Coordinator", "options": [{"Exploitation": "poc"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2025-12-09T20:11:35.267669Z"}}}], "references": [{"url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-hxj9-33pp-j2cc", "tags": ["exploit"]}, {"url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-8vch-m3f4-q8jf", "tags": ["exploit"]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2025-12-09T20:11:40.823Z"}}], "cna": {"title": "Elysia vulnerable to prototype pollution with multiple standalone schema validation", "source": {"advisory": "GHSA-hxj9-33pp-j2cc", "discovery": "UNKNOWN"}, "metrics": [{"cvssV4_0": {"version": "4.0", "baseScore": 9.1, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH"}}], "affected": [{"vendor": "elysiajs", "product": "elysia", "versions": [{"status": "affected", "version": ">= 1.4.0, < 1.4.17"}]}], "references": [{"url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-hxj9-33pp-j2cc", "name": "https://github.com/elysiajs/elysia/security/advisories/GHSA-hxj9-33pp-j2cc", "tags": ["x_refsource_CONFIRM"]}, {"url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-8vch-m3f4-q8jf", "name": "https://github.com/elysiajs/elysia/security/advisories/GHSA-8vch-m3f4-q8jf", "tags": ["x_refsource_MISC"]}, {"url": "https://github.com/elysiajs/elysia/pull/1564", "name": "https://github.com/elysiajs/elysia/pull/1564", "tags": ["x_refsource_MISC"]}, {"url": "https://github.com/elysiajs/elysia/commit/26935bf76ebc43b4a43d48b173fc853de43bb51e", "name": "https://github.com/elysiajs/elysia/commit/26935bf76ebc43b4a43d48b173fc853de43bb51e", "tags": ["x_refsource_MISC"]}, {"url": "https://github.com/elysiajs/elysia/commit/3af978663e437dccc6c1a2a3aff4b74e1574849e", "name": "https://github.com/elysiajs/elysia/commit/3af978663e437dccc6c1a2a3aff4b74e1574849e", "tags": ["x_refsource_MISC"]}], "descriptions": [{"lang": "en", "value": "Elysia is a Typescript framework for request validation, type inference, OpenAPI documentation and client-server communication. Versions 1.4.0 through 1.4.16 contain a prototype pollution vulnerability in `mergeDeep` after merging results of two standard schema validations with the same key. Due to the ordering of merging, there must be an any type that is set as a standalone guard, to allow for the `__proto__ prop` to be merged. When combined with GHSA-8vch-m3f4-q8jf this allows for a full RCE by an attacker. This issue is fixed in version 1.4.17. To workaround, remove the `__proto__ key` from body."}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-1321", "description": "CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2025-12-09T19:43:10.252Z"}}}, "cveMetadata": {"cveId": "CVE-2025-66456", "state": "PUBLISHED", "dateUpdated": "2025-12-09T20:35:44.683Z", "dateReserved": "2025-12-01T22:51:54.580Z", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "datePublished": "2025-12-09T19:43:10.252Z", "assignerShortName": "GitHub_M"}, "dataVersion": "5.2"}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "Elysia is a Typescript framework for request validation, type inference, OpenAPI documentation and client-server communication. Versions 1.4.0 through 1.4.16 contain a prototype pollution vulnerability in `mergeDeep` after merging results of two standard schema validations with the same key. Due to the ordering of merging, there must be an any type that is set as a standalone guard, to allow for the `__proto__ prop` to be merged. When combined with GHSA-8vch-m3f4-q8jf this allows for a full RCE by an attacker. This issue is fixed in version 1.4.17. To workaround, remove the `__proto__ key` from body."}], "id": "CVE-2025-66456", "lastModified": "2025-12-12T15:19:07.567", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 9.1, "baseSeverity": "CRITICAL", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/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", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2025-12-09T20:15:54.760", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/elysiajs/elysia/commit/26935bf76ebc43b4a43d48b173fc853de43bb51e"}, {"source": "security-advisories@github.com", "url": "https://github.com/elysiajs/elysia/commit/3af978663e437dccc6c1a2a3aff4b74e1574849e"}, {"source": "security-advisories@github.com", "url": "https://github.com/elysiajs/elysia/pull/1564"}, {"source": "security-advisories@github.com", "url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-8vch-m3f4-q8jf"}, {"source": "security-advisories@github.com", "url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-hxj9-33pp-j2cc"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-8vch-m3f4-q8jf"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "url": "https://github.com/elysiajs/elysia/security/advisories/GHSA-hxj9-33pp-j2cc"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-1321"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}