CVE-2026-74757 (GCVE-0-2026-74757)

Vulnerability from cvelistv5 – Published: 2026-10-21 11:46 – Updated: 2026-10-21 11:46
VLAI
Title
Apache bRPC: Uncontrolled Memory Allocation via Malicious mcpack Array Item Count
Summary
Uncontrolled resource allocation in the mcpack2pb component in Apache bRPC (version < 1.18.0) on all platforms allows remote attackers to make the server allocate a large amount of memory via sending a crafted mcpack request with a huge array item count. Root Cause: The bRPC mcpack2pb parser trusts the item count stored in the mcpack array header without validating it against the actual payload size. The code generated by the mcpack2pb protoc plugin uses this count to preallocate memory for repeated protobuf fields via Reserve(). A malformed request declaring item_count = 0x7fffffff can force the server to preallocate about 16GB of virtual memory, which may abort the process (SIGABRT) on memory-constrained hosts. Affected Scenarios: Use a bRPC server that wires a NsheadService to UbrpcMcpack2Adaptor (the Baidu ubrpc deployment pattern) and parses requests with code generated by the mcpack2pb protoc plugin. The request body is parsed before authentication. 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/3451 Note: No matter which option you choose, you should know that the fix caps the array item count to the remaining bytes of the array payload.
Severity
No CVSS data available.
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
apache CNA under the mitre root
CNA scorecard B 76/100 over 1086 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache bRPC Affected: 0 , < 1.18.0 (semver)
guessed Create a notification for this product.
Credits
Feng Zhijie (Dopamine)
Show details on NVD website
To clipboard 

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