CVE-2026-105241 (GCVE-0-2026-105241)

Vulnerability from cvelistv5 – Published: 2026-10-06 19:49 – Updated: 2026-10-06 19:49
VLAI
Title
Apache log4net: Unencodable content discards a whole SmtpPickupDirAppender batch
Summary
Improper Handling of Unicode Encoding vulnerability in the SmtpPickupDirAppender of Apache log4net. Content that the mail file writer cannot encode, such as an unpaired UTF-16 surrogate, made the write throw. Every buffered event in the batch was discarded, not only the one carrying the content, and a truncated mail could be left in the pickup directory. A party whose data reaches a log message could suppress the records of other events. Only applications that use SmtpPickupDirAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE
  • CWE-176 - Improper Handling of Unicode Encoding
Assigner
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache log4net Affected: 1.2.9 , < 3.5.0 (semver)
guessed Create a notification for this product.
Apache Software Foundation Apache log4net Affected: 02e1e115435888485f2e28b414d267e39e799e07 , < 4d2e10f0908199604b4326f9df6d0b43b871e333 (git)
guessed Create a notification for this product.
Credits
The Apache Software Foundation Claude Security Jan Friedrich
Show details on NVD website
To clipboard 

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