Security advisory

{
  "id": "33e2247fb12a8702395a30464ddc2c4c7d3f5d6a2dad170581d3612721f33ae0",
  "url": "https://osv.dev/vulnerability/CVE-2021-27645",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-27645",
    "summary": "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.",
    "evidence": "osv:CVE-2021-27645",
    "products": [],
    "severity": "low",
    "structured": {
      "id": "CVE-2021-27645",
      "aliases": [
        "CVE-2021-27645"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/bminor/glibc",
              "type": "GIT",
              "events": [
                {
                  "introduced": "56c86f5dd516284558e106d04b92875d5b623b7a"
                },
                {
                  "last_affected": "9826b03b747b841f5fc6de2054bf1ef3f5c4bdf3"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "2.29"
                      },
                      {
                        "last_affected": "2.33"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "glibc-2.33",
            "glibc-2.32",
            "glibc-2.32.9000",
            "glibc-2.31",
            "glibc-2.31.9000",
            "changelog-ends-here",
            "glibc-2.30",
            "glibc-2.30.9000",
            "glibc-2.29",
            "glibc-2.29.9000"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-27645.json"
          }
        },
        {
          "ranges": [
            {
              "repo": "https://sourceware.org/git/glibc.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "56c86f5dd516284558e106d04b92875d5b623b7a"
                },
                {
                  "last_affected": "9826b03b747b841f5fc6de2054bf1ef3f5c4bdf3"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "2.29"
                      },
                      {
                        "last_affected": "2.33"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "glibc-2.33",
            "glibc-2.32",
            "glibc-2.32.9000",
            "glibc-2.31",
            "glibc-2.31.9000",
            "changelog-ends-here",
            "glibc-2.30",
            "glibc-2.30.9000",
            "glibc-2.29",
            "glibc-2.29.9000"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-27645.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:23.204020796Z",
      "provider": "osv",
      "references": [
        "https://cert-portal.siemens.com/productcert/html/ssa-398330.html",
        "https://cert-portal.siemens.com/productcert/html/ssa-831302.html",
        "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7LZNT6KTMCCWPWXEOGSHD3YLYZKUGMH5/",
        "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I7TS26LIZSOBLGJEZMJX4PXT5BQDE2WS/",
        "https://lists.debian.org/debian-lts-announce/2022/10/msg00021.html",
        "https://security.gentoo.org/glsa/202107-07",
        "https://sourceware.org/bugzilla/show_bug.cgi?id=27462"
      ],
      "provider_metadata": {
        "unresolved_ranges": [
          {
            "cpes": [
              "cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*"
            ],
            "vendor_product": "debian:debian_linux",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "10.0"
                  },
                  {
                    "last_affected": "10.0"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          },
          {
            "cpes": [
              "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*",
              "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*"
            ],
            "vendor_product": "fedoraproject:fedora",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "33"
                  },
                  {
                    "last_affected": "33"
                  },
                  {
                    "introduced": "34"
                  },
                  {
                    "last_affected": "34"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          }
        ]
      }
    },
    "related_cves": [
      {
        "value": "CVE-2021-27645",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 430872,
  "published_at": "2021-02-24T15:15:13.837+00:00"
}