FKIE_CVE-2018-20839

Vulnerability from fkie_nvd - Published: 2019-05-17 04:29 - Updated: 2026-06-17 01:53
Severity
4.3 (Medium) - CVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Summary
systemd 242 changes the VT1 mode upon a logout, which allows attackers to read cleartext passwords in certain circumstances, such as watching a shutdown, or using Ctrl-Alt-F1 and Ctrl-Alt-F2. This occurs because the KDGKBMODE (aka current keyboard mode) check is mishandled.
References
cve@mitre.orghttp://www.securityfocus.com/bid/108389Broken Link, Third Party Advisory, VDB Entry
cve@mitre.orghttps://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1803993Issue Tracking, Third Party Advisory
cve@mitre.orghttps://github.com/systemd/systemd/commit/9725f1a10f80f5e0ae7d9b60547458622aeb322fPatch
cve@mitre.orghttps://github.com/systemd/systemd/pull/12378Issue Tracking, Patch
cve@mitre.orghttps://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3EMailing List
cve@mitre.orghttps://security.netapp.com/advisory/ntap-20190530-0002/Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108http://www.securityfocus.com/bid/108389Broken Link, Third Party Advisory, VDB Entry
af854a3a-2127-422b-91ae-364da2661108https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1803993Issue Tracking, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/systemd/systemd/commit/9725f1a10f80f5e0ae7d9b60547458622aeb322fPatch
af854a3a-2127-422b-91ae-364da2661108https://github.com/systemd/systemd/pull/12378Issue Tracking, Patch
af854a3a-2127-422b-91ae-364da2661108https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3EMailing List
af854a3a-2127-422b-91ae-364da2661108https://security.netapp.com/advisory/ntap-20190530-0002/Third Party Advisory
Impacted products
Vendor Product Version
systemd_project systemd 242
netapp cn1610_firmware -
netapp cn1610 -
netapp snapprotect -
netapp solidfire_\&_hci_management_node -
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
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  ],
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  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "systemd 242 changes the VT1 mode upon a logout, which allows attackers to read cleartext passwords in certain circumstances, such as watching a shutdown, or using Ctrl-Alt-F1 and Ctrl-Alt-F2. This occurs because the KDGKBMODE (aka current keyboard mode) check is mishandled."
    },
    {
      "lang": "es",
      "value": "El systemd 242 cambia el VT1 mode al terminar la sesi\u00f3n, esto permite a los atacantes leer contrase\u00f1as de texto simple en algunas circunstancias, tales como ver un apagado o usar Ctrl-Alt-F1 y Ctrl-Alt-F2. Esto ocurre porque la comprobaci\u00f3n KDGKBMODE (tambi\u00e9n conocido como modo de teclado actual) es manejada incorrectamente."
    }
  ],
  "id": "CVE-2018-20839",
  "lastModified": "2026-06-17T01:53:34.263",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "NONE",
          "baseScore": 4.3,
          "confidentialityImpact": "PARTIAL",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:M/Au:N/C:P/I:N/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 8.6,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
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          "baseScore": 4.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
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          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
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        "source": "nvd@nist.gov",
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  "published": "2019-05-17T04:29:00.933",
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  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Analyzed",
  "weaknesses": [
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      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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