{"id":"CVE-2026-90484","state":"PUBLISHED","title":"Apache bRPC: Null pointer dereference in MySQL reply parser leading to client crash","description":"The MySQL client response parser in Apache bRPC dereferences a null pointer when the server peer sends a zero-payload-length response packet. A response packet whose declared payload length is zero is accepted by the frame-length check (is_full_package), after which the parser reads the response type byte via an unbounded 5-byte fetch that returns nullptr, and type = p[4] dereferences it, crashing the client process.\n\n\n\nRoot Cause: In brpc::policy::MysqlReply::ConsumePartialIOBuf, buf.fetch(header, 5) returns nullptr when the buffered data only holds the 4-byte header of a zero-length packet, then the code reads p[4] (and, in the fast-auth path, p2[4]) without checking for a null or zero-length packet.\n\n\n\nAffected Scenarios: A brpc MySQL client connecting to a malicious or compromised MySQL server (or a MITM) can be crashed by a zero-length server response packet, resulting in denial of service of the client.\n\n\n\nFix: The fix rejects zero-length response packets (returning PARSE_ERROR_ABSOLUTELY_WRONG) both for the initial response type determination and after a fast-auth marker, before reading the type byte. Upgrade to the Apache bRPC version 1.18.0 or apply the PR patch at https://github.com/apache/brpc/pull/3536.","publishedAt":"2026-10-21T12:19:37.796Z","updatedAt":"2026-10-26T13:39:12.101Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"apache","products":["Apache Software Foundation Apache bRPC"],"affected":[{"vendor":"Apache Software Foundation","product":"Apache bRPC","packageName":"apache/brpc","packageURL":"pkg:github/apache/brpc","defaultStatus":"unaffected","versions":[{"version":"<= 1.11.0","status":"affected","lessThan":"1.18.0","versionType":"semver"}],"collectionURL":"https://github.com"}],"references":["https://github.com/apache/brpc/pull/3536","https://lists.apache.org/thread/2pf15ojj0vr7rtx95677kgtl1mx3gdgb"],"weaknesses":["CWE-476"],"ingestedAt":"2026-10-29T20:13:34.582Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/90xxx/CVE-2026-90484.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90484","state":"PUBLISHED","datePublished":"2026-10-21T12:19:37.796Z","dateUpdated":"2026-10-26T13:39:12.101Z","assignerShortName":"apache","assignerOrgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","dateReserved":"2026-09-12T04:06:06.138Z"},"containers":{"cna":{"title":"Apache bRPC: Null pointer dereference in MySQL reply parser leading to client crash","descriptions":[{"lang":"en","value":"The MySQL client response parser in Apache bRPC dereferences a null pointer when the server peer sends a zero-payload-length response packet. A response packet whose declared payload length is zero is accepted by the frame-length check (is_full_package), after which the parser reads the response type byte via an unbounded 5-byte fetch that returns nullptr, and type = p[4] dereferences it, crashing the client process.\n\n\n\nRoot Cause: In brpc::policy::MysqlReply::ConsumePartialIOBuf, buf.fetch(header, 5) returns nullptr when the buffered data only holds the 4-byte header of a zero-length packet, then the code reads p[4] (and, in the fast-auth path, p2[4]) without checking for a null or zero-length packet.\n\n\n\nAffected Scenarios: A brpc MySQL client connecting to a malicious or compromised MySQL server (or a MITM) can be crashed by a zero-length server response packet, resulting in denial of service of the client.\n\n\n\nFix: The fix rejects zero-length response packets (returning PARSE_ERROR_ABSOLUTELY_WRONG) both for the initial response type determination and after a fast-auth marker, before reading the type byte. Upgrade to the Apache bRPC version 1.18.0 or apply the PR patch at https://github.com/apache/brpc/pull/3536."}],"affected":[{"vendor":"Apache Software Foundation","product":"Apache bRPC","packageName":"apache/brpc","packageURL":"pkg:github/apache/brpc","defaultStatus":"unaffected","versions":[{"version":"<= 1.11.0","status":"affected","lessThan":"1.18.0","versionType":"semver"}],"collectionURL":"https://github.com"}],"references":[{"url":"https://github.com/apache/brpc/pull/3536","name":"PR 3536"},{"url":"https://lists.apache.org/thread/2pf15ojj0vr7rtx95677kgtl1mx3gdgb","tags":["vendor-advisory"]}],"metrics":[{"other":{"type":"Textual description of severity","content":{"text":"moderate"}},"scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-476","description":"CWE-476 NULL Pointer Dereference","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"apache","orgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","dateUpdated":"2026-10-21T12:19:37.796Z"},"source":{"discovery":"INTERNAL"},"x_generator":{"engine":"Vulnogram 0.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":6.5,"attackVector":"NETWORK","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-10-26T13:39:08.583202Z","id":"CVE-2026-90484","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-26T13:39:12.101Z"}}]}}}