---
id: CVE-2026-54426
title: 'Apache bRPC: Stack Exhaustion via Unbounded Recursion in Redis Reply Parser'
summary: >-
  Uncontrolled recursion in the Redis reply parser in Apache bRPC < 1.18.0
  allows a remote Redis server peer to crash a bRPC Redis client process by
  returning a deeply nested RESP array reply. The parser recursed once for each
  nested array…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: adp
cwe:
  - CWE-674
vendor: Apache Software Foundation
product: apache/brpc
affected:
  - apache/brpc < 1.18.0
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-30T13:46:36.006598Z'
published: '2026-10-21'
updated: '2026-10-30'
sourceUpdated: '2026-10-30T13:46:51.555Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-54426'
references:
  - url: 'https://lists.apache.org/thread/2pf15ojj0vr7rtx95677kgtl1mx3gdgb'
tags:
  - cve.org
epss: 0.00462
epssPercentile: 0.4013
ingestedAt: '2026-10-21T11:47:58.156Z'
---

## Overview

Uncontrolled recursion in the Redis reply parser in Apache bRPC < 1.18.0 allows a remote Redis server peer to crash a bRPC Redis client process by returning a deeply nested RESP array reply. The parser recursed once for each nested array level without enforcing a depth limit. The fix adds a configurable Redis reply depth limit with default value 128 and rejects replies exceeding that limit. 

Affected Scenarios:
Applications using bRPC as a Redis client with ChannelOptions.protocol="redis" and receiving replies from an untrusted or faulty Redis server peer.

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:
After applying the fix, Redis replies with array nesting deeper than redis_max_reply_depth are rejected.

## Affected

- `apache/brpc < 1.18.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.