CVE-2026-79704
Low risk· EPSS 5%Exploitation Probability (EPSS)
Low risk5th percentile - higher than 5% of all known CVEs
Summary
An out-of-bounds read vulnerability exists in the streaming RPC client of Apache bRPC (versions 1.11.0 through 1.17.0). A client creating multiple streams in a single RPC indexes returned extra_stream_id values without first validating the returned list size, so a malicious or compromised server can return a malformed StreamSettings response with fewer identifiers and trigger an out-of-bounds read.
Risk Assessment
This may crash the client process (denial of service) or leak unintended memory contents into subsequent stream handling. The risk affects clients connecting to an untrusted server or over an untrusted network path.
Recommendation
Upgrade Apache bRPC to version 1.18.0 or apply the patch from PR #3485. The fix rejects responses whose extra_stream_ids count does not exactly match the number of additional client streams.
Other vulnerabilities in Apache bRPC
See all- CVE-2025-60021Critical
Remote command injection vulnerability in heap profiler builtin service in Apache bRPC (all versions < 1.15.0) on all platforms allows attacker to inject remote command. Root Cause: The bRPC heap profiler built-in service (/pprof/heap) does not validate the user-provided extra_options parameter and executes it as a command-line argument. Attackers can execute remote commands using the extra_options parameter. Affected scenarios: Use the built-in bRPC heap profiler service to perform jemalloc memory profiling. How to Fix: we provide two methods, you can choose one of them: 1. Upgrade bRPC to version 1.15.0. 2. Apply this patch ( https://github.com/apache/brpc/pull/3101 ) manually.
- CVE-2026-90484Low risk· EPSS 4%
The MySQL client response parser in Apache bRPC dereferences a null pointer when the server peer sends a zero-payload-length response packet. A packet with declared zero payload length passes the frame-length check, after which the parser reads the response type byte via an unbounded 5-byte fetch that returns nullptr, causing type = p[4] to dereference it and crash the client process.
- CVE-2026-87849Low risk· EPSS 5%
A vulnerability in the Discovery naming-service reply parser in Apache bRPC (versions < 1.18.0) calls RapidJSON object-only accessors (FindMember) on JSON values without first validating that they are objects. A malformed Discovery response whose data/service members or instances list contain non-object entries triggers an out-of-bounds read and potentially crashes the bRPC client.
- CVE-2026-86249Low risk· EPSS 24%
On a brpc::Server that sets both ServerOptions.auth and ServerOptions.internal_port, the HTTP built-in service exemption on internal_port can be abused to bypass authentication entirely. Verification runs only for the first message of a connection and the result latches the connection, so a request such as GET /status to internal_port authenticates the whole connection.
- CVE-2026-86147Low risk· EPSS 10%
Apache bRPC versions before 1.18.0 expose builtin /flags and /pprof services that allow a remote attacker to change dump paths (bvar_dump_file, bvar_dump_tabs, mbvar_dump_file) and create directories or overwrite files with the server process privileges. Additionally, the ?seconds= parameter in /pprof is not clamped, enabling an attacker to hold the process-wide CPU profiler for an arbitrarily long time.
- CVE-2026-86146Low risk· EPSS 10%
HTTP request/response smuggling vulnerability in Apache bRPC versions < 1.18.0 stems from inconsistent HTTP/1.1 header parsing in its bundled parser. bRPC accepts malformed header forms (space before colon, spaces in Content-Length values, obs-fold, chunked trailers merged as headers, Transfer-Encoding lists with whitespace), allowing attackers to smuggle requests or headers when bRPC is deployed behind a proxy or load balancer.
- CVE-2026-84748Low risk· EPSS 7%
Improper authorization in Apache bRPC (versions < 1.18.0) allows remote attackers to access builtin services through the public port. Protobuf-based protocol dispatch paths computed but did not enforce the security_mode flag, allowing invocation of services such as brpc.vars or hotspots.
- CVE-2026-84747Low risk· EPSS 11%
A vulnerability in Apache bRPC (versions < 1.18.0) stems from an interpretation conflict in HTTP path handling between bRPC and a front proxy. The FindMethodPropertyByURI() function skips empty path segments (consecutive slashes), so paths like //flags are dispatched as /flags, even though RFC 3986 treats them as distinct. Additionally, HTTP/2 does not validate the :path pseudo-header, allowing bypass of proxy ACL rules and access to internal services.
- CVE-2026-84727Medium
A use-after-free exists in the RTMP protocol implementation in Apache bRPC (version < 1.18.0). A malicious RTMP peer can crash the process or potentially corrupt memory via a crafted Abort message. The root cause is that the receive path deletes the target RtmpChunkStream object while the send path concurrently dereferences it without synchronization.
- CVE-2026-82953Low risk· EPSS 12%
A NULL pointer dereference in the RTMP protocol implementation in Apache bRPC (versions < 1.18.0) occurs when the server rejects a createStream request by returning a null stream and then fails to write the error response, causing a crash. A remote attacker can trigger a denial of service by sending a crafted createStream command and closing the connection before the rejection response is written.
Original NVD description (English source)
An out-of-bounds read vulnerability exists in the streaming RPC client of Apache bRPC (versions 1.11.0 through 1.17.0) on all platforms. A client that creates multiple streams in a single RPC expects the server response to carry exactly one extra_stream_id for every additional stream. The response handling path indexed the returned identifiers using the locally created stream count without first validating the size of the returned list, so a malicious or compromised server (or an on-path attacker) can trigger an out-of-bounds read in the client by returning a malformed StreamSettings response with fewer extra_stream_ids than expected. This may crash the client process (denial of service) or leak unintended memory contents into subsequent stream handling; surplus identifiers have no valid client-stream mapping and are processed inconsistently. Root Cause: Since bRPC 1.11.0, a client can create multiple streams in one RPC via batch StreamCreate. The expected behavior is that the server response must return exactly (N-1) extra_stream_ids, where N is the number of locally created streams. In Controller::HandleStreamConnection, the response path reads extra_stream_ids[i-1] for each additional local stream without first comparing the returned list size with (N-1). If the server returns fewer identifiers, the read runs past the end of the returned list (out-of-bounds read); if it returns more, the surplus identifiers have no corresponding client-side stream. Affected Scenarios: A bRPC client using multi-stream RPC (creating more than one stream in a single RPC) that connects to an untrusted, malicious, or compromised server or to a server reached through an untrusted network path. The server sends a malformed StreamSettings response to trigger the issue. 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/3485 Note: The fix makes the client reject responses whose extra_stream_ids count does not exactly match the number of additional client streams. Such mismatched responses now fail the RPC with ERESPONSE and go through the existing stream cleanup path, instead of being partially processed.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS