CVE-2026-78058
HighCVSS 7.5Exploitation Probability (EPSS)
Elevated risk57th percentile - higher than 57% of all known CVEs
Summary
Apache bRPC versions < 1.18.0 contain an uncontrolled resource consumption vulnerability in the HTTP/2 (h2) receive path. A remote unauthenticated attacker can send crafted HTTP/2 frames to crash the server or cause unbounded memory growth. The root cause is that receive-side limits (e.g., MAX_CONCURRENT_STREAMS, MAX_HEADER_LIST_SIZE) are advertised but never enforced, and control-frame acks bypass the write buffer cap.
Risk Assessment
Any bRPC server serving HTTP/h2/gRPC to an untrusted network, and any bRPC h2/gRPC client connecting to an untrusted backend, is exposed. An attacker can cause denial of service (crash) or memory exhaustion, and the h2 parser runs before any Authenticator check.
Recommendation
Upgrade Apache bRPC to version 1.18.0 or later, or apply the patch from https://github.com/apache/brpc/pull/3474. After the fix, default limits are enforced: 1024 concurrent streams per connection, 1 MiB decoded header list size per stream, and control-frame acks respect the write buffer cap.
Other vulnerabilities in Apache bRPC
See all- CVE-2026-86249Critical
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-2026-78334Critical
Missing authentication in the streaming RPC path of Apache bRPC (version < 1.18.0) allows a remote attacker to bypass server authentication and inject or deliver streaming frames when a server is configured with an Authenticator. Streaming frames never pass through the authentication hook, and streams can be impersonated by another socket carrying the same id.
- CVE-2026-56388Critical
The Redis server command parser in Apache bRPC accepts an empty RESP array as a command header. A remote unauthenticated attacker can send an empty array header followed by a bulk string, causing an out-of-bounds write in the parser and crashing the process.
- CVE-2026-48830Critical
Improper authentication in Apache bRPC through 1.17.0 allows a remote unauthenticated attacker to bypass authentication for protected builtin HTTP endpoints by first sending a builtin HTTP request on the same HTTP/1.1 keep-alive connection. When ServerOptions.auth is enabled and builtin HTTP services are publicly exposed, the first builtin request may mark the connection as authenticated for later requests.
- 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-2023-31039Critical
Apache bRPC < 1.5.0 on all platforms allows attackers to execute arbitrary code via the ServerOptions::pid_file parameter. An attacker who can influence this parameter when starting the bRPC server can execute arbitrary code with the permissions of the bRPC process.
- CVE-2026-90484Medium
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-2026-87849Medium
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-2026-86147High
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-2026-86146High
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.
Original NVD description (English source)
Uncontrolled resource consumption in the HTTP/2 (h2) receive path of Apache bRPC (version < 1.18.0) on all platforms allows a remote unauthenticated attacker to crash the server or grow its memory without bound by sending crafted HTTP/2 frames. Root Cause: The h2 parser, enabled by default on every bRPC server port and used by h2/gRPC clients, trusts the peer to respect receive-side limits that bRPC advertises but never enforces: 1. SETTINGS_MAX_CONCURRENT_STREAMS defaulted to unlimited and was never checked on the server, letting a peer pin an unbounded number of pending streams per connection (~100x memory amplification). 2. SETTINGS_MAX_HEADER_LIST_SIZE defaulted to unlimited and was never enforced; 1-byte HPACK indexed references amplify a small HEADERS frame ~4000x into an unbounded decoded header list ("HPACK bomb"), and a never-completed HEADERS/CONTINUATION block accumulates memory without limit. 3. Control-frame acks (PING/SETTINGS acks, RST_STREAM, GOAWAY, WINDOW_UPDATE) unconditionally bypassed the -socket_max_unwritten_bytes write cap, so a PING flood combined with withheld TCP reads grew the connection buffer without the documented bound. 4. The HPACK dynamic table size update was validated against the protocol default (4096) instead of the advertised SETTINGS_HEADER_TABLE_SIZE, which together with the dynamic-table queue/accounting issue can desynchronize the decoder and dereference NULL (crash). Affected scenarios: Any bRPC server serving HTTP/h2/gRPC to an untrusted network, and any bRPC h2/gRPC client connecting to an untrusted backend. The h2 parser runs before any Authenticator check on the shared port. How to fix: Upgrade bRPC, or apply the patch in https://github.com/apache/brpc/pull/3474. Note: After applying the fix the following limits are enforced by default: - max_concurrent_streams: 1024 per connection (4294967295 restores unlimited). - max_header_list_size: 1 MiB decoded size per stream (4294967295 restores unlimited; -h2_client_max_header_list_size for clients). - h2 control-frame acks respect -socket_max_unwritten_bytes (-h2_ack_ignore_eovercrowded restores the old behavior). Requests exceeding these limits are rejected (RST_STREAM(REFUSED_STREAM) or a connection error).
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

