CVE-2026-1225 (GCVE-0-2026-1225)

Vulnerability from cvelistv5 – Published: 2026-01-22 09:24 – Updated: 2026-01-22 14:14
VLAI
Title
Malicious logback.xml configuration file allows instantiation of arbitrary classes
Summary
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.
Severity
1.8 (Low)
CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/S:N/AU:N/RE:M/U:Green
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-22 14:14 UTC
CWE
  • CWE-20 - Improper Input Validation
Assigner
NCSC.ch CNA under the mitre root
CNA scorecard B 79/100 over 81 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
QOS.CH Sarl Logback-core Affected: 0.9.20 , ≤ 1.5.24 (maven)
Unaffected: 1.5.25
guessed Create a notification for this product.
Credits
https://www.code-intelligence.com/ Google Fuzz
Show details on NVD website
To clipboard 

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