{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-6091","assignerOrgId":"50d2cd11-d01a-48ed-9441-5bfce9d63b27","state":"PUBLISHED","assignerShortName":"wolfSSL","dateReserved":"2026-04-10T16:01:23.181Z","datePublished":"2026-06-25T16:46:12.599Z","dateUpdated":"2026-06-25T17:58:31.045Z"},"containers":{"cna":{"providerMetadata":{"orgId":"50d2cd11-d01a-48ed-9441-5bfce9d63b27","shortName":"wolfSSL","dateUpdated":"2026-06-25T16:46:12.599Z"},"title":"Partial-chain verification accepts untrusted intermediate as trust anchor","problemTypes":[{"descriptions":[{"lang":"en","cweId":"CWE-295","description":"CWE-295 Improper Certificate Validation","type":"CWE"}]}],"affected":[{"vendor":"wolfSSL","product":"wolfSSL","collectionURL":"https://github.com/wolfSSL/wolfssl","versions":[{"status":"affected","version":"5.7.4","lessThanOrEqual":"5.9.1","versionType":"semver"}],"defaultStatus":"unaffected"}],"descriptions":[{"lang":"en","value":"Partial-chain certificate verification may accept chains that terminate at a peer-supplied, untrusted intermediate certificate rather than a trusted anchor. An attacker could present a chain that ends at an intermediate they control and have it accepted as valid. This affects the OpenSSL compatibility certificate-path-building path (wolfSSL_X509_verify_cert / X509_STORE, OPENSSL_EXTRA) when the X509_V_FLAG_PARTIAL_CHAIN verify flag is enabled.","supportingMedia":[{"type":"text/html","base64":false,"value":"<p>Partial-chain certificate verification may accept chains that terminate at a peer-supplied, untrusted intermediate certificate rather than a trusted anchor. An attacker could present a chain that ends at an intermediate they control and have it accepted as valid. This affects the OpenSSL compatibility certificate-path-building path (wolfSSL_X509_verify_cert / X509_STORE, OPENSSL_EXTRA) when the X509_V_FLAG_PARTIAL_CHAIN verify flag is enabled.</p>"}]}],"references":[{"url":"https://github.com/wolfSSL/wolfssl/pull/10170","tags":["patch"]},{"url":"https://www.wolfssl.com/docs/security-vulnerabilities/"}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"HIGH","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"MEDIUM","baseScore":6,"vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"}}],"credits":[{"lang":"en","value":"Dikai Zou","type":"finder"}],"source":{"discovery":"UNKNOWN"},"x_generator":{"engine":"Vulnogram 1.0.2"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-25T17:58:24.366839Z","id":"CVE-2026-6091","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-06-25T17:58:31.045Z"}}]}}