Technology · Apache
Apache Log4net vulnerabilities
Updated . Rebuilt every hour.
Junglewise Threat Intelligence has tracked 7 vulnerabilities in Apache Log4net: 0 in the last 7 days and 6 in the last 90 days, 0 of them critical and 0 exploited in the wild. The most recent, CVE-2026-105244, was published on 6 October 2026. Nothing in the last four weeks, down from 6 vulnerabilities in the four before.
- Last 7 days
- 0
- Last 90 days
- 6
- Critical, all time
- 0
- Exploited in the wild
- 0
About Apache Log4net
A tool to help the programmer output log statements to a variety of output targets.
Latest Apache Log4net vulnerabilities
- CVE-2026-105244: Apache log4net improper character escaping in RemoteSyslogAppendermediumCVSS 5.3
- CVE-2026-105243: Apache log4net insufficient logging in EventLogAppendermediumCVSS 5.3
- CVE-2026-105242: Apache log4net improper handling of exceptions in aspnet-request pattern convertermediumCVSS 5.3
- CVE-2026-105241: Apache log4net improper Unicode encoding in SmtpPickupDirAppendermediumCVSS 5.3
- CVE-2026-105240: Apache log4net null byte handling in OutputDebugStringAppendermediumCVSS 5.3
- CVE-2026-105239: Apache log4net null byte injection in EventLogAppendermediumCVSS 5.3
- CVE-2026-40021: Apache Log4net log suppression in XmlLayoutmediumCVSS 5.3EPSS 1.0%
Most severe Apache Log4net vulnerabilities
Exploited in the wild first, then by severity and CVSS score.
- CVE-2026-40021: Apache Log4net log suppression in XmlLayoutmediumCVSS 5.3EPSS 1.0%
- CVE-2026-105244: Apache log4net improper character escaping in RemoteSyslogAppendermediumCVSS 5.3
- CVE-2026-105243: Apache log4net insufficient logging in EventLogAppendermediumCVSS 5.3
- CVE-2026-105242: Apache log4net improper handling of exceptions in aspnet-request pattern convertermediumCVSS 5.3
- CVE-2026-105241: Apache log4net improper Unicode encoding in SmtpPickupDirAppendermediumCVSS 5.3
- CVE-2026-105240: Apache log4net null byte handling in OutputDebugStringAppendermediumCVSS 5.3
- CVE-2026-105239: Apache log4net null byte injection in EventLogAppendermediumCVSS 5.3
Vulnerabilities per week
Nothing in the last four weeks, down from 6 vulnerabilities in the four before. The last 13 weeks, by the week each vulnerability was published.
| Week of | Bar | Vulns | Critical |
|---|---|---|---|
| 17 Aug 2026 | 0 | 0 | |
| 24 Aug 2026 | 0 | 0 | |
| 31 Aug 2026 | 0 | 0 | |
| 7 Sep 2026 | 0 | 0 | |
| 14 Sep 2026 | 0 | 0 | |
| 21 Sep 2026 | 0 | 0 | |
| 28 Sep 2026 | 0 | 0 | |
| 5 Oct 2026 | 6 | 0 | |
| 12 Oct 2026 | 0 | 0 | |
| 19 Oct 2026 | 0 | 0 | |
| 26 Oct 2026 | 0 | 0 | |
| 2 Nov 2026 | 0 | 0 | |
| 9 Nov 2026 | 0 | 0 |
Embed a badge
A live badge for a README, a status page or an internal wiki: how many Apache Log4net vulnerabilities were published in the last 7 days and how many of them are critical, refreshed hourly.
[](https://junglewise.ai/threats/technologies/log4net)<a href="https://junglewise.ai/threats/technologies/log4net"><img src="https://junglewise.ai/threats/technologies/log4net/badge.svg" alt="Apache Log4net vulnerabilities" /></a>How this is built
Junglewise Threat Intelligence collects vulnerabilities from NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories, and matches each one to the technologies and vendors it affects. Dates are the date a vulnerability was published, in UTC.
The pages are rebuilt from the database every hour. Frozen weekly and monthly reports never change once published, so they can be cited.
Use this data
The same data is at https://junglewise.ai/threats/technologies/log4net.json, and this page as text at https://junglewise.ai/threats/technologies/log4net.md, for scripts and language models. It is free to reuse under CC BY 4.0 with a link back to this page.
Cite as: Junglewise Threat Intelligence, "Apache Log4net vulnerabilities", https://junglewise.ai/threats/technologies/log4net, 12 November 2026.