Malicious logback.xml configuration file allows instantiation of arbitrary classes (QOS.CH Sarl Logback-core)

CVE-2026-1225
LOW 1.8

At a glance

Source
NVD
EPSS
EPSS 0.16 % · percentile 5 ()
State
PUBLISHED
Published
Updated
Assigner
NCSC.ch
NVD status
Deferred

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.

Weaknesses (CWE)

  • CWE-20 — Improper Input Validation

References

Scores

VersionScoreVectorScored by
CVSS 4.0LOW 1.8CVSS: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:GreenNCSC.ch
CVSS 4.0LOW 1.8CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:N/AU:N/R:X/V:X/RE:M/U:GreenNVD · vulnerability@ncsc.ch (Secondary)

Advisories

European references

CERT-FR advisories

Affected products

ProductVersions
QOS.CH Sarl · Logback-coreaffected 0.9.20 ≤ 1.5.24 ; unaffected 1.5.25

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD