ACE vulnerability in configuration file processing by QOS.CH logback-core up to and including version 1.5.24 in Java applications, allows an attacker to instantiate classes already present on the class path by compromising an existing logback configuration file.
The instantiation of a potentially malicious Java class requires that said class is present on the user's class-path. In addition, the attacker must have write access to a
configuration file. However, after successful instantiation, the instance is very likely to be discarded with no further ado.
The instantiation of a potentially malicious Java class requires that said class is present on the user's class-path. In addition, the attacker must have write access to a
configuration file. However, after successful instantiation, the instance is very likely to be discarded with no further ado.
Metrics
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
Update to logback version 1.5.25 or later.
Workaround
No workaround given by the vendor.
References
| Link | Providers |
|---|---|
| https://logback.qos.ch/news.html#1.5.25 |
|
History
Thu, 22 Jan 2026 12:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Title | Conditional processing of logback.xml configuration file, in conjuction with Spring Framework and Janino | Malicious logback.xml configuration file allows instantiation of arbitrary classes |
Thu, 22 Jan 2026 09:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | ACE vulnerability in configuration file processing by QOS.CH logback-core up to and including version 1.5.24 in Java applications, allows an attacker to instantiate classes already present on the class path by compromising an existing logback configuration file. The instantiation of a potentially malicious Java class requires that said class is present on the user's class-path. In addition, the attacker must have write access to a configuration file. However, after successful instantiation, the instance is very likely to be discarded with no further ado. | |
| Title | Conditional processing of logback.xml configuration file, in conjuction with Spring Framework and Janino | |
| Weaknesses | CWE-20 | |
| References |
| |
| Metrics |
cvssV4_0
|
Projects
Sign in to view the affected projects.
Status: PUBLISHED
Assigner: NCSC.ch
Published:
Updated: 2026-01-22T12:10:39.562Z
Reserved: 2026-01-20T12:29:25.357Z
Link: CVE-2026-1225
No data.
Status : Received
Published: 2026-01-22T10:16:07.693
Modified: 2026-01-22T10:16:07.693
Link: CVE-2026-1225
No data.
OpenCVE Enrichment
No data.
Weaknesses