{"id":"CVE-2026-50161","state":"PUBLISHED","title":"libre: Integer overflow in websock_decode() masked frame length check leads to heap buffer overflow","description":"libre is a generic library for real-time communications with asynchronous input and output support. Prior to 4.8.1, the websock_decode() function in src/websock/websock.c contains an integer overflow when validating a masked WebSocket frame that uses the 64-bit extended length encoding. The expression 4 + hdr->len can wrap when hdr->len is close to UINT64_MAX, causing the mbuf_get_left() bounds check to pass. The subsequent XOR unmasking loop then writes beyond the heap buffer. Applications using websock_accept() or websock_accept_proto() to implement a WebSocket server are affected, and exploitation can cause attacker-controlled heap corruption or denial of service after the HTTP WebSocket upgrade handshake. This issue is fixed in version 4.8.1.","publishedAt":"2026-08-18T17:53:01.696Z","updatedAt":"2026-08-19T15:11:15.350Z","severity":{"score":9.3,"label":"Critical","version":"4.0","vector":"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","source":"GitHub_M"},"assigner":"GitHub_M","products":["baresip re"],"affected":[{"vendor":"baresip","product":"re","versions":[{"version":"< 4.8.1","status":"affected"}]}],"references":["https://github.com/baresip/re/security/advisories/GHSA-hvxv-v2gp-v93h","https://github.com/baresip/re/pull/1584","https://github.com/baresip/re/commit/718b92615c7963670d26c1a2b246968b58d782e8","https://github.com/baresip/re/releases/tag/v4.8.1"],"weaknesses":["CWE-190","CWE-787"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/50xxx/CVE-2026-50161.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-50161","state":"PUBLISHED","datePublished":"2026-08-18T17:53:01.696Z","dateUpdated":"2026-08-19T15:11:15.350Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-03T20:54:20.432Z"},"containers":{"cna":{"title":"libre: Integer overflow in websock_decode() masked frame length check leads to heap buffer overflow","descriptions":[{"lang":"en","value":"libre is a generic library for real-time communications with asynchronous input and output support. Prior to 4.8.1, the websock_decode() function in src/websock/websock.c contains an integer overflow when validating a masked WebSocket frame that uses the 64-bit extended length encoding. The expression 4 + hdr->len can wrap when hdr->len is close to UINT64_MAX, causing the mbuf_get_left() bounds check to pass. The subsequent XOR unmasking loop then writes beyond the heap buffer. Applications using websock_accept() or websock_accept_proto() to implement a WebSocket server are affected, and exploitation can cause attacker-controlled heap corruption or denial of service after the HTTP WebSocket upgrade handshake. This issue is fixed in version 4.8.1."}],"affected":[{"vendor":"baresip","product":"re","versions":[{"version":"< 4.8.1","status":"affected"}]}],"references":[{"url":"https://github.com/baresip/re/security/advisories/GHSA-hvxv-v2gp-v93h","name":"https://github.com/baresip/re/security/advisories/GHSA-hvxv-v2gp-v93h","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/baresip/re/pull/1584","name":"https://github.com/baresip/re/pull/1584","tags":["x_refsource_MISC"]},{"url":"https://github.com/baresip/re/commit/718b92615c7963670d26c1a2b246968b58d782e8","name":"https://github.com/baresip/re/commit/718b92615c7963670d26c1a2b246968b58d782e8","tags":["x_refsource_MISC"]},{"url":"https://github.com/baresip/re/releases/tag/v4.8.1","name":"https://github.com/baresip/re/releases/tag/v4.8.1","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"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","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","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-190","lang":"en","description":"CWE-190: Integer Overflow or Wraparound","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-787","lang":"en","description":"CWE-787: Out-of-bounds Write","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-18T17:53:01.696Z"},"source":{"advisory":"GHSA-hvxv-v2gp-v93h","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-19T15:11:03.181573Z","id":"CVE-2026-50161","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":"2026-08-19T15:11:15.350Z"}}]}}}