{"cve":"CVE-2026-90484","nvd":{"published":"2026-10-21T13:20:56.590","modified":"2026-10-26T14:16:41.463","status":"Deferred","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":6.5},"cwes":["CWE-476"],"references":["https://github.com/apache/brpc/pull/3536","https://lists.apache.org/thread/2pf15ojj0vr7rtx95677kgtl1mx3gdgb"],"products":[],"source":"nvd","synced_at":"2026-10-26T14:43:18.613094146+00:00"},"epss":{"cve":"CVE-2026-90484","score":0.00153,"percentile":0.04354,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}