ghsa-gpxv-776p-7gc7
Vulnerability from github
Published
2022-05-24 17:07
Modified
2022-12-16 22:56
Severity ?
5.8 (Medium) - CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
Summary
Jenkins vulnerable to UDP amplification reflection attack
Details

Jenkins 2.218 and earlier, LTS 2.204.1 and earlier supports two network discovery services (UDP multicast/broadcast and DNS multicast) by default.

The UDP multicast/broadcast service can be used in an amplification reflection attack, as very few bytes sent to the respective endpoint result in much larger responses: A single byte request to this service would respond with more than 100 bytes of Jenkins metadata which could be used in a DDoS attack on a Jenkins controller. Within the same network, spoofed UDP packets could also be sent to make two Jenkins controllers go into an infinite loop of replies to one another, thus causing a denial of service.

Jenkins 2.219, LTS 2.204.2 now disables both UDP multicast/broadcast and DNS multicast by default.

Administrators that need these features can re-enable them again by setting the system property hudson.DNSMultiCast.disabled to false (for DNS multicast) or the system property hudson.udp to 33848, or another port (for UDP broadcast/multicast). These are the same system properties that controlled whether these features were enabled in the past, so any instances explicitly enabling these features by setting these system properties will continue to have them enabled.

Show details on source website

To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.jenkins-ci.main:jenkins-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.204.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.jenkins-ci.main:jenkins-core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.205"
            },
            {
              "fixed": "2.219"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2020-2100"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-406"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2022-12-16T22:56:41Z",
    "nvd_published_at": "2020-01-29T16:15:00Z",
    "severity": "MODERATE"
  },
  "details": "Jenkins 2.218 and earlier, LTS 2.204.1 and earlier supports two network discovery services (UDP multicast/broadcast and DNS multicast) by default.\n\nThe UDP multicast/broadcast service can be used in an amplification reflection attack, as very few bytes sent to the respective endpoint result in much larger responses: A single byte request to this service would respond with more than 100 bytes of Jenkins metadata which could be used in a DDoS attack on a Jenkins controller. Within the same network, spoofed UDP packets could also be sent to make two Jenkins controllers go into an infinite loop of replies to one another, thus causing a denial of service.\n\nJenkins 2.219, LTS 2.204.2 now disables both UDP multicast/broadcast and DNS multicast by default.\n\nAdministrators that need these features can re-enable them again by setting the system property `hudson.DNSMultiCast.disabled` to `false` (for DNS multicast) or the system property `hudson.udp` to `33848`, or another port (for UDP broadcast/multicast). These are the same system properties that controlled whether these features were enabled in the past, so any instances explicitly enabling these features by setting these system properties will continue to have them enabled.",
  "id": "GHSA-gpxv-776p-7gc7",
  "modified": "2022-12-16T22:56:41Z",
  "published": "2022-05-24T17:07:40Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-2100"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jenkinsci/jenkins/commit/cd28a6d9347228b03da0e45653e23032342c2a36"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHBA-2020:0402"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHBA-2020:0675"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2020:0681"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2020:0683"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jenkinsci/jenkins"
    },
    {
      "type": "WEB",
      "url": "https://jenkins.io/security/advisory/2020-01-29/#SECURITY-1641"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2020/01/29/1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Jenkins vulnerable to UDP amplification reflection attack"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.