Is CVE-2026-84747 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-84747 being exploited in the wild.

How severe is CVE-2026-84747?

Informational severity, published 21 October 2026.

How is CVE-2026-84747 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-84747?

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-2026-84747: Apache bRPC HTTP protocol interpretation conflict access control bypass

Q: Is there a fix for CVE-2026-84747?

Yes: fixed in 1.18.0. Until then: After upgrading, HTTP and HTTP/2 requests with empty path segments are rejected by default; deployments that require backward compatibility with the lenient behavior can re-enable it via the gflag -http_allow_empty_path_segments, though this is not recommended for servers exposed to untrusted traffic. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

CVE-2026-84747 · Severity: info · Published 2026-10-21

Apache bRPC is an open-source RPC framework used to build distributed services. When deployed behind a front-end proxy or gateway that enforces access controls, an attacker can bypass those access control rules by sending specially crafted URLs with empty path segments (such as //flags instead of /flags), allowing unauthorized access to restricted built-in services like configuration or status endpoints.

Technologies: Apache Brpc. Vendors: Apache.

Quick answers

Is CVE-2026-84747 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-84747 being exploited in the wild.
How severe is CVE-2026-84747?: Informational severity, published 21 October 2026.
Which products and versions are affected?: Apache Brpc < 1.18.0.
Is there a fix for CVE-2026-84747?: Yes: fixed in 1.18.0. Until then: After upgrading, HTTP and HTTP/2 requests with empty path segments are rejected by default; deployments that require backward compatibility with the lenient behavior can re-enable it via the gflag -http_allow_empty_path_segments, though this is not recommended for servers exposed to untrusted traffic. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-84747 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-84747?: 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: 1.18.0

After upgrading, HTTP and HTTP/2 requests with empty path segments are rejected by default; deployments that require backward compatibility with the lenient behavior can re-enable it via the gflag -http_allow_empty_path_segments, though this is not recommended for servers exposed to untrusted traffic.

Technical details

The vulnerability stems from a path normalization mismatch: bRPC's HTTP protocol implementation strips consecutive slashes from request paths during dispatch, while RFC 3986 treats them as distinct paths. HTTP/2 additionally failed to validate the :path pseudo-header per RFC 9113. An attacker behind a permissive network boundary can send non-normalized paths that pass through a restrictive front proxy but are collapsed and dispatched by bRPC to protected endpoints, effectively bypassing ACL checks on built-in services.

Affected products

Apache bRPC < 1.18.0

Timeline

2026-10-21: disclosed

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.