CVE-2026-40021

N/A

Description

Apache Log4net's XmlLayout https://logging.apache.org/log4net/manual/configuration/layouts.html#layout-list and XmlLayoutSchemaLog4J https://logging.apache.org/log4net/manual/configuration/layouts.html#layout-list , in versions before 3.3.0, fail to sanitize characters forbidden by the XML 1.0 specification https://www.w3.org/TR/xml/#charsets in MDC property keys and values, as well as the identity field that may carry attacker-influenced data. This causes an exception during serialization and the silent loss of the affected log event. An attacker who can influence any of these fields can exploit this to suppress individual log records, impairing audit trails and detection of malicious activity. Users are advised to upgrade to Apache Log4net 3.3.0, which fixes this issue.

Details CVE

Score CVSS v3.1N/A

Publie4/10/2026

Derniere modification4/10/2026

Sourcenvd

Observations honeypot0

Faiblesses (CWE)

CWE-116

References

https://github.com/apache/logging-log4net/pull/280(security@apache.org)

https://lists.apache.org/thread/q8otftjswhk69n3kxslqg7cobr0x4st7(security@apache.org)

https://logging.apache.org/cyclonedx/vdr.xml(security@apache.org)

https://logging.apache.org/log4net/manual/configuration/layouts.html(security@apache.org)

https://logging.apache.org/security.html#CVE-2026-40021(security@apache.org)

http://www.openwall.com/lists/oss-security/2026/04/10/11(af854a3a-2127-422b-91ae-364da2661108)

Correlations IOC

Aucune correlation enregistree

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