CyberSecBulletin
CVE-2026-82425NVD status: Deferred

Apache bRPC: Reachable Assertion

Published Updated By the CyberSecBulletin desk

CVE-2026-82425 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 0.42% 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

A reachable assertion in Apache bRPC (version < 1.18.0) on all platforms allows a malicious remote peer to crash the process, resulting in denial of service. Root Cause: When a Socket with health checking enabled fails, Socket::WaitAndReset closes its file descriptor while the event dispatcher may still be delivering an input event (EPOLLIN/EVFILT_READ) that was fetched for the just-closed fd. If the health check then succeeds and revives the Socket, Socket::Address succeeds again while the fd is still -1 (the next write reconnects on demand). In that window, Socket::OnInputEvent hits CHECK(!(events & EPOLLIN)) (or the kqueue equivalent) because the Socket is addressable but has no fd. CHECK failures terminate the process when bRPC is built with glog or when the gflag -crash_on_fatal_log is enabled (CHECK always terminates in OFFICIAL_BUILD/NDEBUG builds as well). Affected Scenarios: Applications using bRPC clients with health check enabled (-health_check_interval). A malicious remote peer that the client connects to can deliberately abort connections and immediately accept the health check probes, racing connection teardown against health check revival to trigger the assertion and abort the process. 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/3510 Note: After applying the fix, stale input events on a Socket revived without an fd are silently dropped instead of triggering the assertion. No user-visible interface or wire protocol is changed.

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

Spotted an error? Tell us.