CVE-2021-4461

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2021-4461", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2025-10-30T20:08:37.632Z", "datePublished": "2025-10-30T21:16:23.161Z", "dateUpdated": "2025-11-28T19:17:19.543Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unknown", "modules": ["thirdpartyController.do \u2013 `enc` parameter decoding (LightWeightEncoder) and parsing"], "product": "Zhiyuan OA Web Application System", "vendor": "Seeyon", "versions": [{"lessThanOrEqual": "7.0 SP1", "status": "affected", "version": "0", "versionType": "custom"}]}], "cpeApplicability": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:seeyon:zhiyuan_oa_web_application_system:*:*:*:*:*:*:*:*", "versionEndIncluding": "7.0_sp1", "versionStartIncluding": "0", "vulnerable": true}], "negate": false, "operator": "OR"}], "operator": "OR"}], "credits": [{"lang": "en", "type": "finder", "value": "Anonymous User via WeChat"}], "descriptions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "Seeyon Zhiyuan OA Web Application System versions up to and including 7.0 SP1&nbsp;improperly decode and parse the `enc` parameter in thirdpartyController.do. The decoded map values can influence session attributes without sufficient authentication/authorization checks, enabling attackers to assign a session to arbitrary user IDs. VulnCheck has observed this vulnerability being exploited in the wild as of 2025-10-30 at 00:30:40.855917 UTC."}], "value": "Seeyon Zhiyuan OA Web Application System versions up to and including 7.0 SP1\u00a0improperly decode and parse the `enc` parameter in thirdpartyController.do. The decoded map values can influence session attributes without sufficient authentication/authorization checks, enabling attackers to assign a session to arbitrary user IDs. VulnCheck has observed this vulnerability being exploited in the wild as of 2025-10-30 at 00:30:40.855917 UTC."}], "metrics": [{"cvssV4_0": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "baseScore": 9.3, "baseSeverity": "CRITICAL", "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:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"cweId": "CWE-306", "description": "CWE-306 Missing Authentication for Critical Function", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2025-10-30T21:18:19.787Z"}, "references": [{"tags": ["exploit"], "url": "https://mp.weixin.qq.com/s/0AqdfTrZUVrwTMbKEKresg"}, {"tags": ["exploit"], "url": "https://github.com/chaitin/xray/blob/f90cf321bc4d294bbf6625a9c4853f3bfdf0a384/pocs/seeyon-oa-cookie-leak.yml"}, {"tags": ["exploit"], "url": "https://github.com/projectdiscovery/nuclei-templates/blob/1ca6b8e6fe225cbd46dcb893dcaee01447afa8c0/http/misconfiguration/seeyon-unauth.yaml#L20"}, {"tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/seeyon-zhiyuan-oa-web-application-system-authentication-bypass"}], "source": {"discovery": "UNKNOWN"}, "tags": ["x_known-exploited-vulnerability"], "title": "Seeyon Zhiyuan OA Web Application System < 7.0 SP1 Authentication Bypass", "x_generator": {"engine": "Vulnogram 0.4.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2025-11-28T19:16:58.418427Z", "id": "CVE-2021-4461", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"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": "2025-11-28T19:17:19.543Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2021-4461", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2025-11-28T19:16:58.418427Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2025-10-31T18:34:30.657Z"}}], "cna": {"tags": ["x_known-exploited-vulnerability"], "title": "Seeyon Zhiyuan OA Web Application System < 7.0 SP1 Authentication Bypass", "source": {"discovery": "UNKNOWN"}, "credits": [{"lang": "en", "type": "finder", "value": "Anonymous User via WeChat"}], "metrics": [{"format": "CVSS", "cvssV4_0": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 9.3, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "affected": [{"vendor": "Seeyon", "modules": ["thirdpartyController.do \u2013 `enc` parameter decoding (LightWeightEncoder) and parsing"], "product": "Zhiyuan OA Web Application System", "versions": [{"status": "affected", "version": "0", "versionType": "custom", "lessThanOrEqual": "7.0 SP1"}], "defaultStatus": "unknown"}], "references": [{"url": "https://mp.weixin.qq.com/s/0AqdfTrZUVrwTMbKEKresg", "tags": ["exploit"]}, {"url": "https://github.com/chaitin/xray/blob/f90cf321bc4d294bbf6625a9c4853f3bfdf0a384/pocs/seeyon-oa-cookie-leak.yml", "tags": ["exploit"]}, {"url": "https://github.com/projectdiscovery/nuclei-templates/blob/1ca6b8e6fe225cbd46dcb893dcaee01447afa8c0/http/misconfiguration/seeyon-unauth.yaml#L20", "tags": ["exploit"]}, {"url": "https://www.vulncheck.com/advisories/seeyon-zhiyuan-oa-web-application-system-authentication-bypass", "tags": ["third-party-advisory"]}], "x_generator": {"engine": "Vulnogram 0.4.0"}, "descriptions": [{"lang": "en", "value": "Seeyon Zhiyuan OA Web Application System versions up to and including 7.0 SP1\u00a0improperly decode and parse the `enc` parameter in thirdpartyController.do. The decoded map values can influence session attributes without sufficient authentication/authorization checks, enabling attackers to assign a session to arbitrary user IDs. VulnCheck has observed this vulnerability being exploited in the wild as of 2025-10-30 at 00:30:40.855917 UTC.", "supportingMedia": [{"type": "text/html", "value": "Seeyon Zhiyuan OA Web Application System versions up to and including 7.0 SP1&nbsp;improperly decode and parse the `enc` parameter in thirdpartyController.do. The decoded map values can influence session attributes without sufficient authentication/authorization checks, enabling attackers to assign a session to arbitrary user IDs. VulnCheck has observed this vulnerability being exploited in the wild as of 2025-10-30 at 00:30:40.855917 UTC.", "base64": false}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-306", "description": "CWE-306 Missing Authentication for Critical Function"}]}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:seeyon:zhiyuan_oa_web_application_system:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndIncluding": "7.0_sp1", "versionStartIncluding": "0"}], "operator": "OR"}], "operator": "OR"}], "providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2025-10-30T21:18:19.787Z"}}}, "cveMetadata": {"cveId": "CVE-2021-4461", "state": "PUBLISHED", "dateUpdated": "2025-11-28T19:17:19.543Z", "dateReserved": "2025-10-30T20:08:37.632Z", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "datePublished": "2025-10-30T21:16:23.161Z", "assignerShortName": "VulnCheck"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unknown", "modules": ["thirdpartyController.do \u2013 `enc` parameter decoding (LightWeightEncoder) and parsing"], "product": "Zhiyuan OA Web Application System", "vendor": "Seeyon", "versions": [{"lessThanOrEqual": "7.0 SP1", "status": "affected", "version": "0", "versionType": "custom"}]}], "source": "disclosure@vulncheck.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Seeyon Zhiyuan OA Web Application System versions up to and including 7.0 SP1\u00a0improperly decode and parse the `enc` parameter in thirdpartyController.do. The decoded map values can influence session attributes without sufficient authentication/authorization checks, enabling attackers to assign a session to arbitrary user IDs. VulnCheck has observed this vulnerability being exploited in the wild as of 2025-10-30 at 00:30:40.855917 UTC."}], "id": "CVE-2021-4461", "lastModified": "2026-06-17T04:19:48.450", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 9.3, "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:N/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": "disclosure@vulncheck.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2021-4461", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2025-11-28T19:16:58.418427Z", "version": "2.0.3"}}]}, "published": "2025-10-30T22:15:41.633", "references": [{"source": "disclosure@vulncheck.com", "url": "https://github.com/chaitin/xray/blob/f90cf321bc4d294bbf6625a9c4853f3bfdf0a384/pocs/seeyon-oa-cookie-leak.yml"}, {"source": "disclosure@vulncheck.com", "url": "https://github.com/projectdiscovery/nuclei-templates/blob/1ca6b8e6fe225cbd46dcb893dcaee01447afa8c0/http/misconfiguration/seeyon-unauth.yaml#L20"}, {"source": "disclosure@vulncheck.com", "url": "https://mp.weixin.qq.com/s/0AqdfTrZUVrwTMbKEKresg"}, {"source": "disclosure@vulncheck.com", "url": "https://www.vulncheck.com/advisories/seeyon-zhiyuan-oa-web-application-system-authentication-bypass"}], "sourceIdentifier": "disclosure@vulncheck.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-306"}], "source": "disclosure@vulncheck.com", "type": "Secondary"}]}

{}

{"created": "2025-10-31T10:14:04.497324+00:00", "updated": "2025-10-31T10:14:04.497349+00:00", "vendors": ["seeyon", "seeyon$PRODUCT$zhiyuan_oa_web_application_system"]}