CVE-2021-26118Network attack vector

Unauthorized message production via unchecked OpenWire advisories

Published Jan 27, 2021 · Updated Feb 13, 2025

Improper access control in Apache Artemis before 2.16.0 allows remote attackers to bypass session policy via OpenWire advisory creation. The OpenWire protocol head creates advisory messages outside the broker's normal post-office authorization path, so their production receives no policy check. Network access to an OpenWire acceptor is sufficient, and the bypass preserves unauthorized message-production privileges for the entire session.

CVSS severity7.5
High
EPSS probability3.92%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper access control in Apache Artemis before 2.16.0 allows remote attackers to bypass session policy via OpenWire advisory creation. The OpenWire protocol head creates advisory messages outside the broker's normal post-office authorization path, so their production receives no policy check. Network access to an OpenWire acceptor is sufficient, and the bypass preserves unauthorized message-production privileges for the entire session.

The record

CVE
CVE-2021-26118
Published
Jan 27, 2021
Updated
Feb 13, 2025
Vendor
The Apache Software Foundation
Product
Apache Artemis
Classifications
CWE-284, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 27, 2021CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <2.16.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache Artemisversion=unspecified <2.16.0

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:P/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-284Improper Access Control
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo