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

FKIE_CVE-2021-20277

Vulnerability from fkie_nvd - Published: 2021-05-12 14:15 - Updated: 2026-06-17 03:33
Summary
A flaw was found in Samba's libldb. Multiple, consecutive leading spaces in an LDAP attribute can lead to an out-of-bounds memory write, leading to a crash of the LDAP server process handling the request. The highest threat from this vulnerability is to system availability.
References
secalert@redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=1941402Issue Tracking, Third Party Advisory
secalert@redhat.comhttps://lists.debian.org/debian-lts-announce/2021/03/msg00036.htmlMailing List, Third Party Advisory
secalert@redhat.comhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/
secalert@redhat.comhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/
secalert@redhat.comhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/
secalert@redhat.comhttps://security.gentoo.org/glsa/202105-22Third Party Advisory
secalert@redhat.comhttps://security.netapp.com/advisory/ntap-20210326-0007/Third Party Advisory
secalert@redhat.comhttps://www.debian.org/security/2021/dsa-4884Third Party Advisory
secalert@redhat.comhttps://www.samba.org/samba/security/CVE-2021-20277.htmlVendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://bugzilla.redhat.com/show_bug.cgi?id=1941402Issue Tracking, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2021/03/msg00036.htmlMailing List, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/
af854a3a-2127-422b-91ae-364da2661108https://security.gentoo.org/glsa/202105-22Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://security.netapp.com/advisory/ntap-20210326-0007/Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.debian.org/security/2021/dsa-4884Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.samba.org/samba/security/CVE-2021-20277.htmlVendor Advisory
Impacted products

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "samba",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "samba 4.14.1, samba 4.13.6, samba 4.12.13"
            }
          ]
        }
      ],
      "source": "secalert@redhat.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "F2EE6834-8738-446C-BD67-B1D69AD8DFAE",
              "versionEndExcluding": "4.12.13",
              "versionStartIncluding": "4.0.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "54588EC1-AE17-47FD-AFB7-70AB43A49515",
              "versionEndExcluding": "4.13.6",
              "versionStartIncluding": "4.13.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "4B8145B4-A320-40A3-A24B-3DE0A0170639",
              "versionEndExcluding": "4.14.1",
              "versionStartIncluding": "4.14.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "DEECE5FC-CACF-4496-A3E7-164736409252",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "07B237A9-69A3-4A9C-9DA0-4E06BD37AE73",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*",
              "matchCriteriaId": "36D96259-24BD-44E2-96D9-78CE1D41F956",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*",
              "matchCriteriaId": "E460AA51-FCDA-46B9-AE97-E6676AA5E194",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*",
              "matchCriteriaId": "A930E247-0B43-43CB-98FF-6CE7B8189835",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in Samba\u0027s libldb. Multiple, consecutive leading spaces in an LDAP attribute can lead to an out-of-bounds memory write, leading to a crash of the LDAP server process handling the request. The highest threat from this vulnerability is to system availability."
    },
    {
      "lang": "es",
      "value": "Se encontr\u00f3 un fallo en libldb de Samba. M\u00faltiples espacios iniciales consecutivos en un atributo LDAP pueden conllevar a una escritura de memoria fuera de los l\u00edmites, conllevando a un bloqueo del proceso del servidor LDAP que maneja la petici\u00f3n. La mayor amenaza de esta vulnerabilidad es la disponibilidad del sistema"
    }
  ],
  "id": "CVE-2021-20277",
  "lastModified": "2026-06-17T03:33:35.570",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 5.0,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 10.0,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-05-12T14:15:11.140",
  "references": [
    {
      "source": "secalert@redhat.com",
      "tags": [
        "Issue Tracking",
        "Third Party Advisory"
      ],
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1941402"
    },
    {
      "source": "secalert@redhat.com",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "https://lists.debian.org/debian-lts-announce/2021/03/msg00036.html"
    },
    {
      "source": "secalert@redhat.com",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/"
    },
    {
      "source": "secalert@redhat.com",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/"
    },
    {
      "source": "secalert@redhat.com",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/"
    },
    {
      "source": "secalert@redhat.com",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://security.gentoo.org/glsa/202105-22"
    },
    {
      "source": "secalert@redhat.com",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://security.netapp.com/advisory/ntap-20210326-0007/"
    },
    {
      "source": "secalert@redhat.com",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.debian.org/security/2021/dsa-4884"
    },
    {
      "source": "secalert@redhat.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.samba.org/samba/security/CVE-2021-20277.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Issue Tracking",
        "Third Party Advisory"
      ],
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1941402"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "https://lists.debian.org/debian-lts-announce/2021/03/msg00036.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://security.gentoo.org/glsa/202105-22"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://security.netapp.com/advisory/ntap-20210326-0007/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.debian.org/security/2021/dsa-4884"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.samba.org/samba/security/CVE-2021-20277.html"
    }
  ],
  "sourceIdentifier": "secalert@redhat.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ],
      "source": "secalert@redhat.com",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

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.

Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


Loading…