GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

GHSA-VC5P-V9HR-52MJ

Vulnerability from github – Published: 2025-12-18 21:31 – Updated: 2025-12-19 22:08
VLAI
Summary
Apache Log4j does not verify the TLS hostname in its Socket Appender
Details

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 configuration attribute or the 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.

Severity
6.3 (Medium)
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
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.apache.logging.log4j:log4j-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.0-beta9"
            },
            {
              "fixed": "2.25.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-68161"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-297"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-12-19T22:08:02Z",
    "nvd_published_at": "2025-12-18T21:15:57Z",
    "severity": "MODERATE"
  },
  "details": "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.\n\nThis issue may allow a man-in-the-middle attacker to intercept or redirect log traffic under the following conditions:\n\n  *  The attacker is able to intercept or redirect network traffic between the client and the log receiver.\n  *  The attacker can present a server certificate issued by a certification authority trusted by the Socket Appender\u2019s configured trust store (or by the default Java trust store if no custom trust store is configured).\n\n\nUsers are advised to upgrade to Apache Log4j Core version 2.25.3, which addresses this issue.\n\nAs an alternative mitigation, the Socket Appender may be configured to use a private or restricted trust root to limit the set of trusted certificates.",
  "id": "GHSA-vc5p-v9hr-52mj",
  "modified": "2025-12-19T22:08:02Z",
  "published": "2025-12-18T21:31:44Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-68161"
    },
    {
      "type": "WEB",
      "url": "https://github.com/apache/logging-log4j2/pull/4002"
    },
    {
      "type": "WEB",
      "url": "https://github.com/apache/logging-log4j2/commit/3b93748497e1adbbd027fda8a5e7268ec5d0d578"
    },
    {
      "type": "WEB",
      "url": "https://github.com/apache/logging-log4j2"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread/xr33kyxq3sl67lwb61ggvm1fzc8k7dvx"
    },
    {
      "type": "WEB",
      "url": "https://logging.apache.org/cyclonedx/vdr.xml"
    },
    {
      "type": "WEB",
      "url": "https://logging.apache.org/log4j/2.x/manual/appenders/network.html#SslConfiguration-attr-verifyHostName"
    },
    {
      "type": "WEB",
      "url": "https://logging.apache.org/log4j/2.x/manual/systemproperties.html#log4j2.sslVerifyHostName"
    },
    {
      "type": "WEB",
      "url": "https://logging.apache.org/security.html#CVE-2025-68161"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2025/12/18/1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Apache Log4j does not verify the TLS hostname in its Socket Appender"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.