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FKIE_CVE-2021-27645

Vulnerability from fkie_nvd - Published: 2021-02-24 15:15 - Updated: 2026-06-17 03:45
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
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.
References
cve@mitre.orghttps://lists.debian.org/debian-lts-announce/2022/10/msg00021.htmlMailing List, Third Party Advisory
cve@mitre.orghttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7LZNT6KTMCCWPWXEOGSHD3YLYZKUGMH5/
cve@mitre.orghttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I7TS26LIZSOBLGJEZMJX4PXT5BQDE2WS/
cve@mitre.orghttps://security.gentoo.org/glsa/202107-07Third Party Advisory
cve@mitre.orghttps://sourceware.org/bugzilla/show_bug.cgi?id=27462Issue Tracking, Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2022/10/msg00021.htmlMailing List, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7LZNT6KTMCCWPWXEOGSHD3YLYZKUGMH5/
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I7TS26LIZSOBLGJEZMJX4PXT5BQDE2WS/
af854a3a-2127-422b-91ae-364da2661108https://security.gentoo.org/glsa/202107-07Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://sourceware.org/bugzilla/show_bug.cgi?id=27462Issue Tracking, Patch, Third Party Advisory
Impacted products
Vendor Product Version
gnu glibc *
fedoraproject fedora 33
fedoraproject fedora 34
debian debian_linux 10.0
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
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      ],
      "source": "cve@mitre.org"
    }
  ],
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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    },
    {
      "lang": "es",
      "value": "El demonio de almacenamiento en cach\u00e9 nameserver (nscd) en el GNU C Library (tambi\u00e9n se conoce como glibc o libc6) versiones 2.29 hasta 2.33, cuando se procesa una petici\u00f3n de b\u00fasqueda de netgroup, puede cometer un fallo debido a una doble liberaci\u00f3n, potencialmente resultando en un servicio degradado o denegaci\u00f3n de servicio en el sistema local.\u0026#xa0;Esto est\u00e1 relacionado con el archivo netgroupcache.c"
    }
  ],
  "id": "CVE-2021-27645",
  "lastModified": "2026-06-17T03:45:17.370",
  "metrics": {
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        "acInsufInfo": false,
        "baseSeverity": "LOW",
        "cvssData": {
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          "accessVector": "LOCAL",
          "authentication": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 1.9,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:L/AC:M/Au:N/C:N/I:N/A:P",
          "version": "2.0"
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        "exploitabilityScore": 3.4,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
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        "source": "nvd@nist.gov",
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          "role": "CISA Coordinator",
          "timestamp": "2025-06-09T14:57:29.856656Z",
          "version": "2.0.3"
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}



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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

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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.
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  • 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.


Detection rules are retrieved from Rulezet.


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