GHSA-P6XC-XR62-6R2G

Vulnerability from github – Published: 2021-12-18 18:00 – Updated: 2026-06-09 10:26
VLAI
Summary
Apache Log4j2 vulnerable to Improper Input Validation and Uncontrolled Recursion
Details

Apache Log4j2 versions 2.0-alpha1 through 2.16.0 (excluding 2.12.3) did not protect from uncontrolled recursion from self-referential lookups. This allows an attacker with control over Thread Context Map data to cause a denial of service when a crafted string is interpreted. This issue was fixed in Log4j 2.17.0 and 2.12.3.

Affected packages

Only the org.apache.logging.log4j:log4j-core package is directly affected by this vulnerability. The org.apache.logging.log4j:log4j-api should be kept at the same version as the org.apache.logging.log4j:log4j-core package to ensure compatability if in use.

Severity
8.6 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.apache.logging.log4j:log4j-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.4.0"
            },
            {
              "fixed": "2.12.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.apache.logging.log4j:log4j-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.13.0"
            },
            {
              "fixed": "2.17.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.apache.logging.log4j:log4j-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.ops4j.pax.logging:pax-logging-log4j2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.8.0"
            },
            {
              "fixed": "1.9.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.ops4j.pax.logging:pax-logging-log4j2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.10.0"
            },
            {
              "fixed": "1.10.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.ops4j.pax.logging:pax-logging-log4j2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.11.0"
            },
            {
              "fixed": "1.11.12"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.ops4j.pax.logging:pax-logging-log4j2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.0.0"
            },
            {
              "fixed": "2.0.13"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-45105"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-20",
      "CWE-674"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-12-18T17:59:37Z",
    "nvd_published_at": "2021-12-18T12:15:00Z",
    "severity": "HIGH"
  },
  "details": "Apache Log4j2 versions 2.0-alpha1 through 2.16.0 (excluding 2.12.3) did not protect from uncontrolled recursion from self-referential lookups. This allows an attacker with control over Thread Context Map data to cause a denial of service when a crafted string is interpreted. This issue was fixed in Log4j 2.17.0 and 2.12.3.\n\n\n# Affected packages\nOnly the `org.apache.logging.log4j:log4j-core` package is directly affected by this vulnerability. The `org.apache.logging.log4j:log4j-api` should be kept at the same version as the `org.apache.logging.log4j:log4j-core` package to ensure compatability if in use.",
  "id": "GHSA-p6xc-xr62-6r2g",
  "modified": "2026-06-09T10:26:50Z",
  "published": "2021-12-18T18:00:07Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-45105"
    },
    {
      "type": "WEB",
      "url": "https://www.zerodayinitiative.com/advisories/ZDI-21-1541"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpujul2022.html"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpujan2022.html"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
    },
    {
      "type": "WEB",
      "url": "https://www.kb.cert.org/vuls/id/930724"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2021/dsa-5024"
    },
    {
      "type": "WEB",
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-log4j-qRuKNEbd"
    },
    {
      "type": "WEB",
      "url": "https://security.netapp.com/advisory/ntap-20211218-0001"
    },
    {
      "type": "WEB",
      "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-log4j-qRuKNEbd"
    },
    {
      "type": "WEB",
      "url": "https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0032"
    },
    {
      "type": "WEB",
      "url": "https://logging.apache.org/log4j/2.x/security.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/SIG7FZULMNK2XF6FZRU4VWYDQXNMUGAJ"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/EOKPQGV24RRBBI4TBZUDQMM4MEH7MXCY"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2021/12/msg00017.html"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-501673.pdf"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-479842.pdf"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2021/12/19/1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Apache Log4j2 vulnerable to Improper Input Validation and Uncontrolled Recursion"
}



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