Number: AL25-002
Date: March 19, 2025
Audience
This Alert is intended for IT professionals and managers.
Purpose
An Alert is used to raise awareness of a recently identified cyber threat that may impact cyber information assets, and to provide additional detection and mitigation advice to recipients. The Canadian Centre for Cyber Security ("Cyber Centre") is also available to provide additional assistance regarding the content of this Alert to recipients as requested.
Details
On March 10, 2025, Apache published a security advisoryFootnote 1 regarding vulnerability (CVE-2025-24813) impacting the Apache Tomcat web server software in the following versions:
- Apache Tomcat – versions 11.0.0-M1 to 11.0.2
- Apache Tomcat – versions 10.1.0-M1 to 10.1.34
- Apache Tomcat – versions 9.0.0.M1 to 9.0.98
This vulnerability could allow a malicious actor to view or inject arbitrary content to security-sensitive files or achieve remote code execution. The exploit does not require authentication and is caused by Tomcat accepting partial PUT requests and its default session persistenceFootnote 2Footnote 3
Additionally, Apache states that the following conditions are required for a malicious actor to view or inject content into security sensitive filesFootnote 1:
- writes enabled for the default servlet (disabled by default)
- support for partial PUT (enabled by default)
- a target URL for security sensitive uploads that was a sub-directory of a target URL for public uploads
- attacker knowledge of the names of security sensitive files being uploaded
- the security sensitive files also being uploaded via partial PUT
Apache also states that the following conditions are required for a malicious actor to achieve remote code executionFootnote 1:
- writes enabled for the default servlet (disabled by default)
- support for partial PUT (enabled by default)
- application was using Tomcat's file based session persistence with the default storage location
- application included a library that may be leveraged in a deserialization attack
In response to this advisory, the Cyber Centre released advisory AV25-127 on March 10Footnote 4.
Suggested Actions
Organizations should review their configurations in determining their risk. They should also verify if they are running any vulnerable versions of Apache Tomcat.
Organizations are advised to update to the following versions of Apache TomcatFootnote 1:
- Apache Tomcat – version 11.0.3 or later
- Apache Tomcat – version 10.1.35 or later
- Apache Tomcat – version 9.0.99 or later
Organizations should also review and implement the Cyber Centre’s Top 10 IT Security Actions Footnote 5 with an emphasis on the following topics:
- Consolidating, monitoring, and defending Internet gateways.
- Patch operating systems and applications.
- Isolate web-facing applications.
- Harden operating systems and applications.
Determine if associated malicious activity has occurred in potentially vulnerable systems. Should this be the case, recipients are encouraged to report via the My Cyber Portal, or email contact@cyber.gc.ca.