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Back to active CVEs
Unknown severity · Source severity not reportedCVE-2026-54427

Apache bRPC: Stack Exhaustion via Unbounded Recursion in AMF ParserCVE-2026-54427

Answer in brief

CVE-2026-54427 records a Unknown severity vulnerability in Apache bRPC: Stack Exhaustion via Unbounded Recursion in AMF Parser. The current sources do not mark it as known exploited. The current feed maps Apache Software Foundation/apache/brpc (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 21, 2026Updated Oct 21, 2026Source checked Oct 21, 2026First seen by HOL Oct 21, 2026Material review Oct 21, 2026
Upstream Advisory

Key facts

Risk
Unknown severitySource severity not reported
Exploitation
Not marked as known exploited
Affected software
1 mapped package or product
Fix availability
Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Apache Software Foundation/apache/brpc (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
PackageAffected rangeFixed version
Apache Software Foundation/apache/brpcgeneric>=0 <1.18.01.18.0

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for Apache Software Foundation/apache/brpc.
  2. 2Review the reported fix. Update Apache Software Foundation/apache/brpc to 1.18.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Oct 21, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  2. Source modified

    Oct 21, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  3. First seen by HOL

    Oct 21, 2026

Sources and claim methodology

  • Source referencelists.apache.org
Upstream source description

Uncontrolled recursion in the AMF parser in Apache bRPC < 1.18.0 allows a remote RTMP peer to crash a bRPC process by sending deeply nested AMF objects or arrays. The parser recursively processed nested AMF containers without enforcing a depth limit, which could exhaust the native stack. Affected Scenarios: Applications using bRPC RTMP support and parsing AMF data from an untrusted RTMP peer. This includes RTMP servers parsing client command messages, RTMP clients parsing server responses or status messages, and either side parsing inbound AMF script data such as metadata or cue points. Direct callers of ReadAMFObject or ReadAMFArray on untrusted input are also affected. How to Fix: 1. Upgrade Apache bRPC to 1.18.0. 2. Apply the patch from PR https://github.com/apache/brpc/pull/3344 . Note: The fix introduces a configurable AMF nesting depth limit with default value 128. AMF objects or arrays deeper than amf_max_depth are rejected after applying the fix.

Quoted source text, attributed separately from HOL analysis.

Related CVEs

  • Apache bRPC: Unbounded Resource Consumption and Crash in the HTTP/2 Receive PathSame apache software foundation/apache/brpc package
  • Apache bRPC: Resource Exhaustion via Unbounded Decompression and Unvalidated Wire-Declared SizesSame apache software foundation/apache/brpc package
  • Apache bRPC: Missing Authentication for Streaming RPC FramesSame apache software foundation/apache/brpc package
  • Apache bRPC: Out-of-bounds Read in Multi-stream RPC Response HandlingSame apache software foundation/apache/brpc package
  • Apache bRPC: Unbounded Memory Accumulation in Stream Message ReassemblySame apache software foundation/apache/brpc package
  • Apache bRPC: Uncontrolled Resource Consumption via Excessive Streams in a Single RPC RequestSame apache software foundation/apache/brpc package

Record context

Vulnerability class
Vulnerability
EPSS
Not reported
CWE IDs
CWE-674
Source
CVE List V5
Source checked
Oct 21, 2026
References
1 linked source
Open source record