CVE-2026-90484 — Apache bRPC: Null pointer dereference in MySQL reply parser leading to client crash
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. Root 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. Affected 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. Fix: 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.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Apache Software Foundation Brpc).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Apache Software Foundation | Brpc | ≥ <= 1.11.0 and < 1.18.0 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 22, 2026 → Oct 23, 2026 · 2 reading(s) · max 0.15%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Source status changed · Received → Deferred
- Source status changed · Published → Received
- Record published
- Source status changed · → Published
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 21, 2026 – Oct 21, 2026
References
2 on the record
Elsewhere on this site
Related CVEs (same products)
- Unknown CVE-2026-87849 Apache bRPC: Out-of-bounds read via non-object fields in Discovery naming-service reply parsing 3d
- Unknown CVE-2026-86249 Apache bRPC: Authentication bypass when a server sets ServerOptions.internal_port and ServerOptions.auth 3d
- Unknown CVE-2026-86147 Apache bRPC: Arbitrary file creation/truncation via /flags and unbounded profiling duration via /pprof 3d
- Unknown CVE-2026-86146 Apache bRPC: HTTP Request Smuggling and Header Injection via Lenient HTTP/1.1 Header Parsing 3d
- Unknown CVE-2026-82425 Apache bRPC: Reachable Assertion in Socket::OnInputEvent Allows Remote Denial of Service 3d
- Unknown CVE-2026-82953 Apache bRPC: NULL Pointer Dereference in RTMP createStream Error Path Leading to Remote Denial of Service 3d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-90484 is "Apache bRPC: Null pointer dereference in MySQL reply parser leading to client crash", rated Unknown. It affects Brpc (Apache Software Foundation); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.15% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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