Vulnerability · Published Dec 18, 2025 · Assigned by apache
CVE-2025-68161Apache Log4j Core: Missing TLS hostname verification in Socket appender
Medium 6.3
In plain English
A medium-severity security flaw in Apache Log4j Core from Apache Software Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 56% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
The Socket Appender in Apache Log4j Core versions 2.0-beta9 through 2.25.2 does not perform TLS hostname verification of the peer certificate, even when the verifyHostName https://logging.apache.org/log4j/2.x/manual/appenders/network.html#SslConfiguration-attr-verifyHostName configuration attribute or the log4j2.sslVerifyHostName https://logging.apache.org/log4j/2.x/manual/systemproperties.html#log4j2.sslVerifyHostName system property is set to true. This issue may allow a man-in-the-middle attacker to intercept or redirect log traffic under the following conditions: * The attacker is able to intercept or redirect network traffic between the client and the log receiver. * The attacker can present a server certificate issued by a certification authority trusted by the Socket Appender’s configured trust store (or by the default Java trust store if no custom trust store is configured). Users are advised to upgrade to Apache Log4j Core version 2.25.3, which addresses this issue. As an alternative mitigation, the Socket Appender may be configured to use a private or restricted trust root to limit the set of trusted certificates.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | apache-log4j2 | no fix listed | DEBIAN-CVE-2025-68161 |
| Debian:13 | apache-log4j2 | no fix listed | DEBIAN-CVE-2025-68161 |
| Debian:14 | apache-log4j2 | no fix listed | DEBIAN-CVE-2025-68161 |
| Maven | org.apache.logging.log4j:log4j-core | 2.25.3 | GHSA-vc5p-v9hr-52mj |
| Ubuntu:22.04:LTS | apache-log4j2 | no fix listed | UBUNTU-CVE-2025-68161 |
| Ubuntu:24.04:LTS | apache-log4j2 | no fix listed | UBUNTU-CVE-2025-68161 |
| Ubuntu:25.10 | apache-log4j2 | no fix listed | UBUNTU-CVE-2025-68161 |
| Ubuntu:26.04:LTS | apache-log4j2 | no fix listed | UBUNTU-CVE-2025-68161 |
| Ubuntu:26.10 | apache-log4j2 | no fix listed | UBUNTU-CVE-2025-68161 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Apache Software Foundation | Apache Log4j Core | 2.0-beta9 – before 2.25.33.0.0-alpha1 – through 3.0.0-beta3 |
Weakness: CWE-297 · Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:L/SA:N
References
- https://github.com/apache/logging-log4j2/pull/4002 patch
- https://logging.apache.org/security.html#CVE-2025-68161 vendor-advisory
- https://logging.apache.org/cyclonedx/vdr.xml vendor-advisory
- https://logging.apache.org/log4j/2.x/manual/systemproperties.html#log4j2.sslVerifyHostName related
- https://logging.apache.org/log4j/2.x/manual/appenders/network.html#SslConfiguration-attr-verifyHostName related
- https://lists.apache.org/thread/xr33kyxq3sl67lwb61ggvm1fzc8k7dvx vendor-advisory
- http://www.openwall.com/lists/oss-security/2025/12/18/1
- https://lists.debian.org/debian-lts-announce/2026/01/msg00015.html