How severe is CVE-2026-33227?

CVE-2026-33227 has a CVSS score of 4.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which products are affected by CVE-2026-33227?

Affected package information for CVE-2026-33227 is not yet fully mapped. Check the official advisory links for details.

How do I patch CVE-2026-33227?

Apply the apache activemq security patch or hotfix for CVE-2026-33227 on the affected version, following the vendor advisory for your exact build.

How do I detect CVE-2026-33227 across my infrastructure?

Inventory every apache activemq deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.

How do I mitigate CVE-2026-33227 if there is no patch (or I can't update yet)?

Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.

How does O3 Security protect against CVE-2026-33227?

O3 detects and blocks CVE-2026-33227 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.

Is CVE-2026-33227 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-33227 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-33227?

CVE-2026-33227 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 33th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-33227?

CVE-2026-33227 is classified as Path Traversal (CWE-22). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Which products and versions are affected by CVE-2026-33227?

CVE-2026-33227 affects apache activemq; apache activemq broker; apache activemq web. Check the affected-products list on this page against your deployed version to confirm exposure.

When was CVE-2026-33227 published, and has it been updated?

CVE-2026-33227 was published on April 7, 2026 and was last updated on June 17, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2026-33227

MEDIUM

Improper validation and restriction of a classpath path name vulnerability in Apache ActiveMQ Client, Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ Web, Apache ActiveMQ. In…

Published

Apr 7, 2026

Updated

Jun 17, 2026

Affected

0 pkgs

Patched

None yet

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk33th percentile+0.34%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

Improper validation and restriction of a classpath path name vulnerability in

Apache ActiveMQ Client, Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ Web, Apache ActiveMQ.

In two instances (when creating a Stomp consumer and also browsing messages in the Web console) an authenticated user provided "key" value could be constructed to traverse the classpath due to path concatenation. As a result, the application is exposed to a classpath path resource loading vulnerability that could potentially be chained together with another attack to lead to exploit.

This issue affects Apache ActiveMQ Client: before 5.19.3, from 6.0.0 before 6.2.2; Apache ActiveMQ Broker: before 5.19.3, from 6.0.0 before 6.2.2; Apache ActiveMQ All: before 5.19.3, from 6.0.0 before 6.2.2; Apache ActiveMQ Web: before 5.19.3, from 6.0.0 before 6.2.2; Apache ActiveMQ: before 5.19.3, from 6.0.0 before 6.2.2.

Users are recommended to upgrade to version 5.19.4 or 6.2.3, which fixes the issue. Note: 5.19.3 and 6.2.2 also fix this issue, but that is limited to non-Windows environments due to a path separator resolution bug fixed in 5.19.4 and 6.2.3.

Affected Products

3 products · 6 configurations

Application

activemqapache

≥ 6.0.0 && < 6.2.2

range

Application

activemq brokerapache

≥ 6.0.0 && < 6.2.2

range

Application

activemq webapache

≥ 6.0.0 && < 6.2.2

range

Detection & mitigation playbook

Vendor / appliance

Detect
Inventory every apache activemq deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Fix
Apply the apache activemq security patch or hotfix for CVE-2026-33227 on the affected version, following the vendor advisory for your exact build.
Workarounds
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2026-33227 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.

Tailored to CVE-2026-33227. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Improper validation and restriction of a classpath path name vulnerability in Apache ActiveMQ Client, Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ Web, Apache ActiveMQ. In two instances (when creating a Stomp consumer and also browsing messages in the Web console) an authenticated user provided "key" value could be constructed to traverse the classpath due to path concatenation. As a result, the application is exposed to a classpath path resource loading vulnerability that could potentially be chained together with another attack to lead to exploit. This issue affect

O3 Security · Runtime Protection

Is CVE-2026-33227 being exploited in your environment?

O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2026-33227 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.

Protect my workloads How runtime protection works

CVE-2026-33227

EPSS Exploitation Probability

Description

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

How O3 protects you

Frequently Asked Questions

Is CVE-2026-33227 being exploited in your environment?