CVE-2026-34477
EPSS 0.03%Apache Log4j Core: `verifyHostName` attribute silently ignored in TLS configuration
描述
The fix for CVE-2025-68161 was incomplete: it addressed hostname verification only when enabled via the [`log4j2.sslVerifyHostName`](https://logging.apache.org/log4j/2.x/manual/systemproperties.html#log4j2.sslVerifyHostName) system property, but not when configured through the [`verifyHostName`](https://logging.apache.org/log4j/2.x/manual/appenders/network.html#SslConfiguration-attr-verifyHostName) attribute of the `<Ssl>` element. Although the `verifyHostName` configuration attribute was introduced in Log4j Core 2.12.0, it was silently ignored in all versions through 2.25.3, leaving TLS connections vulnerable to interception regardless of the configured value. A network-based attacker may be able to perform a man-in-the-middle attack when all of the following conditions are met: * An SMTP, Socket, or Syslog appender is in use. * TLS is configured via a nested <Ssl> element. * The attacker can present a certificate issued by a CA trusted by the appender's configured trust store, or by the default Java trust store if none is configured. This issue does not affect users of the HTTP appender, which uses a separate [`verifyHostname`](https://logging.apache.org/log4j/2.x/manual/appenders/network.html#HttpAppender-attr-verifyHostName) attribute that was not subject to this bug and verifies host names by default. Users are advised to upgrade to Apache Log4j Core 2.25.4, which corrects this issue.
受影響套件(1)
- Maven/org.apache.logging.log4j:log4j-core>= 2.12.0, < 2.25.4
CVSS 分數
| 來源 | 版本 | 嚴重程度 | 向量 |
|---|---|---|---|
| osv | CVSS 4.0 | — | 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 |
參考連結(7)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-34477
- PATCHhttps://github.com/apache/logging-log4j2
- WEBhttps://github.com/apache/logging-log4j2/pull/4075
- WEBhttps://lists.apache.org/thread/lkx8cl46t2bvkcwfcb2pd43ygc097lq4
- WEBhttps://logging.apache.org/cyclonedx/vdr.xml
- WEBhttps://logging.apache.org/log4j/2.x/manual/appenders/network.html#SslConfiguration-attr-verifyHostName
- WEBhttps://logging.apache.org/security.html#CVE-2026-34477