{"id":"CVE-2026-5460","state":"PUBLISHED","title":"Heap Use-After-Free in PQC Hybrid KeyShare Error Cleanup in wolfSSL TLS 1.3","description":"A heap use-after-free exists in wolfSSL's TLS 1.3 post-quantum cryptography (PQC) hybrid KeyShare processing. In the error handling path of TLSX_KeyShare_ProcessPqcHybridClient() in src/tls.c, the inner function TLSX_KeyShare_ProcessPqcClient_ex() frees a KyberKey object upon encountering an error. The caller then invokes TLSX_KeyShare_FreeAll(), which attempts to call ForceZero() on the already-freed KyberKey, resulting in writes of zero bytes over freed heap memory.","publishedAt":"2026-04-09T23:29:27.577Z","updatedAt":"2026-04-10T13:51:18.283Z","severity":{"score":6.3,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N","source":"wolfSSL"},"assigner":"wolfSSL","products":["wolfSSL wolfSSL"],"affected":[{"vendor":"wolfSSL","product":"wolfSSL","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"5.9.1","versionType":"semver"}],"repo":"https://github.com/wolfSSL/wolfssl","programFiles":["src/tls.c"]}],"references":["https://github.com/wolfssl/wolfssl/pull/10092"],"weaknesses":["CWE-416"],"ingestedAt":"2026-10-29T20:12:32.778Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/5xxx/CVE-2026-5460.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-5460","state":"PUBLISHED","datePublished":"2026-04-09T23:29:27.577Z","dateUpdated":"2026-04-10T13:51:18.283Z","assignerShortName":"wolfSSL","assignerOrgId":"50d2cd11-d01a-48ed-9441-5bfce9d63b27","dateReserved":"2026-04-02T22:57:35.093Z"},"containers":{"cna":{"title":"Heap Use-After-Free in PQC Hybrid KeyShare Error Cleanup in wolfSSL TLS 1.3","descriptions":[{"lang":"en","value":"A heap use-after-free exists in wolfSSL's TLS 1.3 post-quantum cryptography (PQC) hybrid KeyShare processing. In the error handling path of TLSX_KeyShare_ProcessPqcHybridClient() in src/tls.c, the inner function TLSX_KeyShare_ProcessPqcClient_ex() frees a KyberKey object upon encountering an error. The caller then invokes TLSX_KeyShare_FreeAll(), which attempts to call ForceZero() on the already-freed KyberKey, resulting in writes of zero bytes over freed heap memory."}],"affected":[{"vendor":"wolfSSL","product":"wolfSSL","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"5.9.1","versionType":"semver"}],"repo":"https://github.com/wolfSSL/wolfssl","programFiles":["src/tls.c"]}],"references":[{"url":"https://github.com/wolfssl/wolfssl/pull/10092"}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"LOW","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":6.3,"vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-416","lang":"en","description":"CWE-416 Use After Free","type":"CWE"}]}],"providerMetadata":{"shortName":"wolfSSL","orgId":"50d2cd11-d01a-48ed-9441-5bfce9d63b27","dateUpdated":"2026-04-09T23:29:27.577Z"},"credits":[{"lang":"en","value":"Calvin Young (eWalker Consulting Inc.)","type":"finder"},{"lang":"en","value":"Enoch Chow (Isomorph Cyber)","type":"finder"}],"source":{"discovery":"EXTERNAL"},"x_generator":{"engine":"Vulnogram 1.0.1"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-10T13:51:11.637858Z","id":"CVE-2026-5460","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-04-10T13:51:18.283Z"}}]}}}