# log4net (NuGet) vulnerabilities

3 known vulnerabilities (1 medium), with the versions each affects and the releases that fix them.

## At a glance

- Latest release: not known (cve.now hasn't read this package's releases)
- Newest unaffected release: not known without release data
- Registry: https://www.nuget.org/packages/log4net

## Advisories (3)

### [CVE-2026-40021](https://cve.now/CVE-2026-40021): Apache Log4net: Silent log event loss in XmlLayout and XmlLayoutSchemaLog4J due to unescaped XML 1.0 forbidden characters

- Severity: Medium 6.3
- Published: Apr 10, 2026
- Affected: fixed in 3.3.0; fixed in 3.3.0.

### [CVE-2018-1285](https://cve.now/CVE-2018-1285): Apache log4net versions before 2.0.10 do not disable XML external entities when parsing log4net configuration files.

- Severity: Unrated
- Published: May 11, 2020
- Affected: fixed in 2.0.10.

### [CVE-2006-0743](https://cve.now/CVE-2006-0743): Format string vulnerability in LocalSyslogAppender in Apache log4net 1.2.9 might allow remote attackers to cause a denial of service…

- Severity: Unrated
- Published: Mar 9, 2006
- Affected: fixed in 1.2.10.

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