CVE Catalog

CVE-2026-78066

Low risk· EPSS 5%
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.16%

5th percentile - higher than 5% of all known CVEs

Summary

Resource exhaustion vulnerability in Apache bRPC versions before 1.18.0 affects multiple parsers that accept wire-controlled input. The gzip/zlib/snappy decompressors enforce no output limit, and the AMF, RTMP, sofa-pbrpc, and mcpack2pb parsers trust wire-declared sizes, allowing attackers to cause disproportionate memory use and crash the process.

Risk Assessment

An attacker can send a crafted request to a bRPC service, causing memory exhaustion and denial of service. The risk applies to any organization exposing bRPC services to untrusted clients.

Recommendation

Upgrade Apache bRPC to version 1.18.0 or apply the patch from PR #3476. After the fix, consider adjusting the -max_decompressed_body_size and max_body_size flags if larger values are legitimately required.

Other vulnerabilities in Apache bRPC

See all
Original NVD description (English source)

Resource exhaustion in Apache bRPC (version < 1.18.0) on all platforms: multiple parsers that accept wire-controlled input bound no limit on the sizes declared by the client or on decompressed output, which attackers can use to drive disproportionate memory use and crash the process. Root Cause: 1) The gzip/zlib/snappy decompressors enforce no output limit: -max_body_size is checked against the compressed bytes only, so a cap-compliant body (e.g. 64 MiB) can decompress to tens of GiB. 2) The AMF string readers allocate the declared length before the bytes are actually available. 3) RTMP chunk headers may re-declare a message length mid-stream; the declared length was never bounded and the partial reassembly buffer kept growing. 4) The sofa-pbrpc parser does not bound meta_size. 5) mcpack2pb trusts wire-declared item counts for Reserve() and a string value_size of 0 underflows the buffer size, aborting the process. Affected Scenarios: Any bRPC service accepting gzip/zlib/snappy-compressed bodies or rtmp, sofa-pbrpc, or mcpack2pb messages from untrusted clients. How to Fix:(Choose one of the following options) 1. Upgrade bRPC to version 1.18.0, which fixes this issue. 2. Apply this patch: https://github.com/apache/brpc/pull/3476 Note: After the fix, requests whose decompressed size, RTMP message length, or mcpack declared count exceed the new limits are rejected. Operators who legitimately need larger values can raise the corresponding flag (-max_decompressed_body_size, max_body_size).

Vulnerability data from NVD (NIST) · CISA KEV · EPSS