---
id: "CVE-2026-54426"
kind: "vulnerability"
aliases: ["CVE-2026-54426"]
title: "Apache bRPC: deeply nested Redis reply crashes the client process"
severity: "medium"
cvss: null
epss: 0.00159
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["brpc", "c++", "package", "redis", "self-hosted"]
not_affected_if: ["no-redis-client", "trusted-redis-server"]
published_at: "2026-10-21T12:17:21+00:00"
first_seen_at: "2026-10-23T21:57:28+00:00"
updated_at: "2026-10-25T05:02:51+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-54426", "first_seen_at": "2026-10-23T21:57:28+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-54426", "first_seen_at": "2026-10-24T13:15:54+00:00"}]
---

# Apache bRPC: deeply nested Redis reply crashes the client process

Apache bRPC's Redis reply parser recurses once per nested array level with no depth limit. A malicious or faulty Redis server can send a deeply nested RESP array reply and crash the bRPC client process.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the bRPC version in use; affected versions are below `1.18.0`.
- Search application code for `ChannelOptions.protocol="redis"` to find bRPC Redis clients.

## Fix

- Upgrade Apache bRPC to `1.18.0`.
- Alternatively, apply the patch from https://github.com/apache/brpc/pull/3344.

## Timeline

- 2026-10-23T21:57:28+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-54426
- 2026-10-24T13:15:54+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-54426

## From the sources

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.

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