
CVE-2026-105241 | Apache log4net | Medium Unicode encoding errors in SmtpPickupDirAppender can discard buffered log events. Fixed in 3.5.0. Details and official source: https://vulnipulse.com/advisories/apache-cve-2026-105241
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NVD description
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.
Priority
LOW
Exploitation
NONE
PoC
NONE
Patch
NONE
Momentum
NONE

CVE-2026-105241 | Apache log4net | Medium Unicode encoding errors in SmtpPickupDirAppender can discard buffered log events. Fixed in 3.5.0. Details and official source: https://vulnipulse.com/advisories/apache-cve-2026-105241