CVE-2025-11226: Conditional processing of logback.xml configuration file, in conjuction with Spring Framework and Janino
ACE vulnerability in conditional configuration file processing by QOS.CH logback-core up to and including version 1.5.18 in Java applications, allows an attacker to execute arbitrary code by compromising an existing logback configuration file or by injecting an environment variable before program execution.
A successful attack requires the presence of Janino library and Spring Framework to be present on the user's class path. In addition, the attacker must have write access to a
configuration file. Alternatively, the attacker could inject a malicious
environment variable pointing to a malicious configuration file. In both
cases, the attack requires existing privilege.
Security readout for executives and security teams
Plain-English summary
CVE-2025-11226 affects Logback configuration processing in certain Java applications. An attacker who already has significant access could make the application run malicious code by altering Logback configuration or influencing startup environment variables. This is serious, but it is not a remote, unauthenticated internet exploit based on the provided sources.
Executive priority
Prioritize systems where Java applications combine Logback, Spring, and Janino and where build, deployment, or runtime configuration can be changed by many users. Treat this as a high-priority hardening and patch-management issue, not evidence of an active internet-wide campaign.
Technical view
Logback-core up to and including 1.5.18 is described as vulnerable during conditional logback.xml processing when Janino and Spring Framework are on the classpath. Exploitation requires attacker write access to an existing configuration file or pre-execution environment-variable injection pointing to a malicious configuration file. CVSS v4.0 score is 7.0, with local attack vector and high privileges required.
Likely exposure
Exposure is most likely in Java applications using logback-core, Spring Framework, and Janino together, especially where deployment users, CI/CD jobs, containers, or operators can modify Logback configuration or startup environment variables.
Exploitation context
The source bundle does not show CISA KEV listing or cited evidence of active exploitation. The described attack requires existing privilege and specific runtime dependencies, limiting broad drive-by exposure but increasing concern for insider, supply-chain, or compromised-build scenarios.
Researcher notes
Key constraints matter: local attack vector, high privileges required, and prerequisite Janino plus Spring classpath. The public description centers on conditional configuration processing and CWE-20. Version metadata in the bundle is imperfect, so rely on the CVE text and QOS.CH release notes for final affected/fixed version decisions.
Mitigation direction
Check QOS.CH Logback guidance and update to the recommended maintained release.
Restrict write access to logback.xml and related configuration paths.
Prevent untrusted users from controlling application startup environment variables.
Remove Janino from the runtime classpath if it is not required.
Review CI/CD and container definitions for unauthorized Logback configuration overrides.
Validation and detection
Inventory applications using logback-core and record exact versions.
Identify applications that also include Spring Framework and Janino.
Check whether logback.xml or equivalent configuration is writable by non-admin users.
Review startup environment variables that influence Logback configuration loading.
Confirm remediation against QOS.CH release notes and dependency lockfiles.
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Potential ATT&CK relevance
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
cwe · low confidence lookup
CWE-20: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
1CVSS vectors
3Timeline events
1ADP providers
2Source links
SSVC decision data
CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: total
CVSS vector scores
1 official score
We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
CWE-20 · source CWE mapping
Improper Input Validation
Improper Input Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.