CVE-2026-88899

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-88899", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-09-10T11:28:50.297Z", "datePublished": "2026-09-10T15:28:51.729Z", "dateUpdated": "2026-09-11T20:33:42.233Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-09-11T11:07:57.696Z"}, "datePublic": "2026-09-09T00:00:00.000Z", "title": "knowns before 0.31.0 External Control of Agent Working Directory via x-opencode-directory Header", "descriptions": [{"lang": "en", "value": "knowns versions before 0.31.0 fail to properly validate the x-opencode-directory request header in the /api/opencode proxy endpoint. Remote attackers can supply arbitrary directory paths to execute file operations outside the project root on the host system."}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "External Control of File Name or Path", "cweId": "CWE-73", "type": "CWE"}]}], "affected": [{"vendor": "knowns-dev", "product": "knowns", "defaultStatus": "unaffected", "packageURL": "pkg:npm/knowns", "versions": [{"version": "0", "status": "affected", "versionType": "semver", "lessThan": "0.31.0"}, {"version": "0.31.0", "status": "unaffected", "versionType": "semver"}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 9.3, "baseSeverity": "CRITICAL"}}, {"format": "CVSS", "cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL"}}], "references": [{"url": "https://github.com/knowns-dev/knowns/security/advisories/GHSA-9h2q-r9fh-f98w", "tags": ["vendor-advisory"], "name": "GitHub Security Advisory (GHSA-9h2q-r9fh-f98w)"}, {"url": "https://github.com/knowns-dev/knowns/blob/v0.30.0/internal/server/server.go#L1283-L1296", "tags": ["technical-description"]}, {"url": "https://github.com/knowns-dev/knowns/commit/37db0561b37b48b8bd035a417d7f1da6258ae657", "tags": ["patch"]}, {"url": "https://github.com/knowns-dev/knowns/releases/tag/v0.31.0", "tags": ["release-notes"], "name": "knowns v0.31.0 Release Notes"}, {"name": "VulnCheck Advisory: knowns before 0.31.0 External Control of Agent Working Directory via x-opencode-directory Header", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/knowns-before-0.31.0-external-control-of-agent-working-directory-via-x-opencode-directory-header"}], "credits": [{"lang": "en", "value": "Tong Hoang Gia (uziii2208)", "type": "finder"}], "x_generator": {"engine": "vulncheck-endgame"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-09-11T17:11:17.124340Z", "id": "CVE-2026-88899", "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": "2026-09-11T20:33:42.233Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"cna": {"title": "knowns before 0.31.0 External Control of Agent Working Directory via x-opencode-directory Header", "credits": [{"lang": "en", "type": "finder", "value": "Tong Hoang Gia"}], "metrics": [{"format": "CVSS", "cvssV4_0": {"version": "4.0", "baseScore": 9.3, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH"}}, {"format": "CVSS", "cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}}], "affected": [{"vendor": "knowns-dev", "product": "knowns", "versions": [{"status": "affected", "version": "0", "lessThan": "0.31.0", "versionType": "semver"}, {"status": "unaffected", "version": "0.31.0", "versionType": "semver"}], "packageURL": "pkg:npm/knowns", "defaultStatus": "unaffected"}], "datePublic": "2026-09-09T00:00:00.000Z", "references": [{"url": "https://github.com/knowns-dev/knowns/security/advisories/GHSA-9h2q-r9fh-f98w", "name": "GitHub Security Advisory (GHSA-9h2q-r9fh-f98w)", "tags": ["vendor-advisory"]}, {"url": "https://github.com/knowns-dev/knowns/blob/v0.30.0/internal/server/server.go#L1283-L1296", "tags": ["technical-description"]}, {"url": "https://github.com/knowns-dev/knowns/commit/37db0561b37b48b8bd035a417d7f1da6258ae657", "tags": ["patch"]}, {"url": "https://github.com/knowns-dev/knowns/releases/tag/v0.31.0", "name": "knowns v0.31.0 Release Notes", "tags": ["release-notes"]}, {"url": "https://www.vulncheck.com/advisories/knowns-before-0.31.0-external-control-of-agent-working-directory-via-x-opencode-directory-header", "name": "VulnCheck Advisory: knowns before 0.31.0 External Control of Agent Working Directory via x-opencode-directory Header", "tags": ["third-party-advisory"]}], "x_generator": {"engine": "vulncheck-endgame"}, "descriptions": [{"lang": "en", "value": "knowns versions before 0.31.0 fail to properly validate the x-opencode-directory request header in the /api/opencode proxy endpoint. Remote attackers can supply arbitrary directory paths to execute file operations outside the project root on the host system."}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-73", "description": "External Control of File Name or Path"}]}], "providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-09-10T15:28:51.729Z"}}, "adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-88899", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-09-11T17:11:17.124340Z"}}}], "providerMetadata": {"shortName": "CISA-ADP", "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "dateUpdated": "2026-09-11T17:11:18.203Z"}}]}, "cveMetadata": {"cveId": "CVE-2026-88899", "state": "PUBLISHED", "dateUpdated": "2026-09-10T15:28:51.729Z", "dateReserved": "2026-09-10T11:28:50.297Z", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "datePublished": "2026-09-10T15:28:51.729Z", "assignerShortName": "VulnCheck"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "packageURL": "pkg:npm/knowns", "product": "knowns", "vendor": "knowns-dev", "versions": [{"lessThan": "0.31.0", "status": "affected", "version": "0", "versionType": "semver"}, {"status": "unaffected", "version": "0.31.0", "versionType": "semver"}]}], "source": "disclosure@vulncheck.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "knowns versions before 0.31.0 fail to properly validate the x-opencode-directory request header in the /api/opencode proxy endpoint. Remote attackers can supply arbitrary directory paths to execute file operations outside the project root on the host system."}], "id": "CVE-2026-88899", "lastModified": "2026-09-11T21:17:55.460", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "disclosure@vulncheck.com", "type": "Secondary"}], "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: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", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "disclosure@vulncheck.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-88899", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-09-11T17:11:17.124340Z", "version": "2.0.3"}}]}, "published": "2026-09-10T16:18:12.120", "references": [{"source": "disclosure@vulncheck.com", "url": "https://github.com/knowns-dev/knowns/blob/v0.30.0/internal/server/server.go#L1283-L1296"}, {"source": "disclosure@vulncheck.com", "url": "https://github.com/knowns-dev/knowns/commit/37db0561b37b48b8bd035a417d7f1da6258ae657"}, {"source": "disclosure@vulncheck.com", "url": "https://github.com/knowns-dev/knowns/releases/tag/v0.31.0"}, {"source": "disclosure@vulncheck.com", "url": "https://github.com/knowns-dev/knowns/security/advisories/GHSA-9h2q-r9fh-f98w"}, {"source": "disclosure@vulncheck.com", "url": "https://www.vulncheck.com/advisories/knowns-before-0.31.0-external-control-of-agent-working-directory-via-x-opencode-directory-header"}], "sourceIdentifier": "disclosure@vulncheck.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-73"}], "source": "disclosure@vulncheck.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,0.31.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "0.31.0"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "knowns", "source": "cna", "vendor": "knowns-dev"}, "product": "knowns", "vendor": "knowns-dev"}], "created": "2026-09-10T16:45:17.329122+00:00", "updated": "2026-09-11T09:15:17.788723+00:00", "vendors": ["knowns-dev", "knowns-dev$PRODUCT$knowns"]}