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CVE-2026-82210NVD status: Deferred

Apache bRPC: Reachable Assertion

CVE-2026-82210 is a high-severity reachable assertion vulnerability in Apache bRPC from Apache, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 1.18.0 as the first without the flaw, so updating Apache bRPC to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.5% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Apache bRPC to 1.18.0 or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
ApacheApache bRPCbefore 1.18.01.18.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CISA (ADP).

Official description

Enforceable assertion in the streaming feature of Apache bRPC (version < 1.18.0) on all platforms allows a remote attacker to crash the server process by sending a malformed stream feedback frame. Root Cause: When handling FRAME_TYPE_FEEDBACK frames, bRPC calls Stream::SetRemoteConsumed() which contains CHECK(_cur_buf_size > 0) and unconditionally asserts CHECK(buf.IsEmpty()) on the frame payload. A feedback frame that carries an unexpected payload, or a feedback frame received on a stream where flow control is disabled (cur_buf_size == 0), reaches these assertions. On failure, CHECK failures abort the process, allowing an unauthenticated single client (once a stream is established) to terminate the server and cause a denial of service. Affected Scenarios: Use bRPC server with the streaming control feature (Stream API) served from untrusted network. How to Fix: 1. Upgrade bRPC to version 1.18.0, which fixes this issue. 2. Apply this patch: https://github.com/apache/brpc/pull/3494 The fix rejects malformed feedback frames with EPROTO and closes only the affected stream instead of crashing the whole process, and it bounds buffer shrinking so cur_buf_size never drops to 0 while flow control is enabled.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Reachable Assertion

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

How developers prevent this class of flaw

  • If the assertion statement is required (e.g., for security or reliability), change the invoking code to avoid the conditions that trigger the assertion.
  • Consider changing the assertion to some other less fatal error. This might not be easy to implement, since other code may be needed to handle the error.
  • Make sensitive open/close operations non-reachable from directly user-controlled data (e.g. open/close resources)

More Reachable Assertion vulnerabilities (CWE-617)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Apache bRPC

All Apache bRPC vulnerabilities

Recent Reachable Assertion vulnerabilities

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