ubuntu-cve-2021-27645
Vulnerability from osv_ubuntu
Published
2021-02-24 15:15
Modified
2026-04-22 07:39
Summary
Details

The nameserver caching daemon (nscd) in the GNU C Library (aka glibc or libc6) 2.29 through 2.33, when processing a request for netgroup lookup, may crash due to a double-free, potentially resulting in degraded service or Denial of Service on the local system. This is related to netgroupcache.c.

Severity
2.5 (Low)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
2.5 (Low)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
N/A (UNKNOWN)
low
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "glibc-source",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc-bin",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-amd64",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-armel",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-dev-armel",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-dev-s390",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-i386",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-lse",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-pic",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-prof",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-s390",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "libc6-x32",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "locales",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "locales-all",
            "binary_version": "2.31-0ubuntu9.7"
          },
          {
            "binary_name": "nscd",
            "binary_version": "2.31-0ubuntu9.7"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "glibc",
        "purl": "pkg:deb/ubuntu/glibc@2.31-0ubuntu9.7?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.31-0ubuntu9.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.30-0ubuntu2",
        "2.30-0ubuntu3",
        "2.31-0ubuntu5",
        "2.31-0ubuntu6",
        "2.31-0ubuntu7",
        "2.31-0ubuntu9",
        "2.31-0ubuntu9.1",
        "2.31-0ubuntu9.2",
        "2.31-0ubuntu9.3"
      ]
    }
  ],
  "aliases": [],
  "details": "The nameserver caching daemon (nscd) in the GNU C Library (aka glibc or libc6) 2.29 through 2.33, when processing a request for netgroup lookup, may crash due to a double-free, potentially resulting in degraded service or Denial of Service on the local system. This is related to netgroupcache.c.",
  "id": "UBUNTU-CVE-2021-27645",
  "modified": "2026-04-22T07:39:57Z",
  "published": "2021-02-24T15:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-27645"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5310-1"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-27645"
    }
  ],
  "related": [
    "USN-5310-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "low",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-27645"
  ]
}



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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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