CVE-2026-54427

Apache bRPC: Stack Exhaustion via Unbounded Recursion in AMF Parser

Published Oct 21, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Apache
Apache brpc
Vendors & Products Apache
Apache brpc
Type Values Removed Values Added
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.
Title Apache bRPC: Stack Exhaustion via Unbounded Recursion in AMF Parser
Weaknesses CWE-674
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
apache
Published
Updated
Oct 30, 2026, 1:54 PM
Reserved
Jun 14, 2026, 7:59 AM
Status
Deferred
Published
Oct 21, 2026, 12:17 PM
Modified
Oct 30, 2026, 2:17 PM