Is CVE-2026-80463 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-80463 being exploited in the wild.

How severe is CVE-2026-80463?

Informational severity, published 21 October 2026.

How is CVE-2026-80463 attacked?

It is attacked over the network.

Am I affected by CVE-2026-80463?

Check whether you run Apache Brpc at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-80463: Apache bRPC unbounded memory accumulation in stream reassembly

Q: Is there a fix for CVE-2026-80463?

Yes: fixed in Apache bRPC 1.18.0. Until then: Apply the patch from https://github.com/apache/brpc/pull/3489, or upgrade to version 1.18.0. After patching, adjust the gflag max_body_size if legitimate fragmented messages larger than the default 64MB limit need to be accepted. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

CVE-2026-80463 · Severity: info · Published 2026-10-21

Apache bRPC is an open-source RPC framework used to build distributed services. A vulnerability in its stream message handling allows a remote attacker to exhaust server memory by sending an endless sequence of message fragments, causing the service to crash or become unavailable. Services accepting streams from untrusted clients are affected.

Technologies: Apache Brpc. Vendors: Apache.

Quick answers

Is CVE-2026-80463 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-80463 being exploited in the wild.
How severe is CVE-2026-80463?: Informational severity, published 21 October 2026.
Which products and versions are affected?: Apache Brpc < 1.18.0.
Is there a fix for CVE-2026-80463?: Yes: fixed in Apache bRPC 1.18.0. Until then: Apply the patch from https://github.com/apache/brpc/pull/3489, or upgrade to version 1.18.0. After patching, adjust the gflag max_body_size if legitimate fragmented messages larger than the default 64MB limit need to be accepted. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-80463 attacked?: It is attacked over the network.
Am I affected by CVE-2026-80463?: Check whether you run Apache Brpc at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: Apache bRPC 1.18.0

Apply the patch from https://github.com/apache/brpc/pull/3489, or upgrade to version 1.18.0. After patching, adjust the gflag max_body_size if legitimate fragmented messages larger than the default 64MB limit need to be accepted.

Technical details

The stream message reassembly path in bRPC accumulates continuation frames into a buffer without size limits, while individual frames are bounded by max_body_size. An attacker with network access to open a stream can send unlimited continuation frames to cause unbounded memory accumulation, leading to denial of service. The fix caps accumulated payload at max_body_size and closes the stream with EMSGSIZE error when exceeded.

Affected products

Apache bRPC < 1.18.0

Timeline

2026-10-21: disclosed

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