Answer in brief
CVE-2026-84747 records a Unknown severity vulnerability in Apache bRPC: Access Control Bypass via HTTP Request Paths Containing Empty Path Segments. The current sources do not mark it as known exploited. The current feed maps Apache Software Foundation/apache/brpc (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Apache Software Foundation/apache/brpc (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Apache Software Foundation/apache/brpcgeneric | >=0 <1.18.0 | 1.18.0 |
Published upstream
Oct 21, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 21, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 21, 2026
Interpretation conflict in the HTTP protocol implementation in Apache bRPC (version < 1.18.0) on all platforms allows remote attackers to bypass access control rules enforced by a front proxy. Root Cause: The method dispatch function FindMethodPropertyByURI() in bRPC's HTTP protocol splits the request path with a string splitter that skips empty fields, so paths containing empty path segments (consecutive slashes), such as //flags, /flags// and /flags//port, are dispatched to the same method as their collapsed form /flags. Per RFC 3986 these are distinct paths. A front proxy that enforces an ACL (e.g. blocking access to builtin services such as /flags) matches the collapsed form only, and therefore forwards the padded literal to the bRPC server, where it is dispatched as if it were the collapsed form. This differential allows //flags?setvalue= to reach a builtin service that /flags is not allowed to reach. Additionally, the HTTP/2 implementation never validated the :path pseudo-header, so requests without a :path, or with a :path that neither begins with '/' nor is the asterisk-form '*', contrary to RFC 9113 section 8.3.1, were not rejected. Affected Scenarios: Deployments of Apache bRPC behind a front proxy or gateway that performs access control (ACL) decisions on the literal request path, where the bRPC server accepts HTTP or HTTP/2 traffic from that proxy. In such deployments an attacker can send a path containing empty path segments to reach a resource that the front proxy intended to block. 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/3512 Note: After applying the fix, HTTP and HTTP/2 request paths containing empty path segments (consecutive slashes) are rejected by default, and HTTP/2 :path values that are empty or neither begin with '/' nor equal '*' are rejected. Deployments that depend on the previous lenient behavior can restore it by turning on the gflag -http_allow_empty_path_segments, which is not recommended for servers exposed to untrusted traffic.
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