Vulnerability-Lookup

GHSA-9GXQ-WFG7-72X4

Vulnerability from github – Published: 2022-05-24 17:39 – Updated: 2025-11-04 21:30

Details

A flaw was found in dnsmasq before version 2.83. When getting a reply from a forwarded query, dnsmasq checks in forward.c:reply_query(), which is the forwarded query that matches the reply, by only using a weak hash of the query name. Due to the weak hash (CRC32 when dnsmasq is compiled without DNSSEC, SHA-1 when it is) this flaw allows an off-path attacker to find several different domains all having the same hash, substantially reducing the number of attempts they would have to perform to forge a reply and get it accepted by dnsmasq. This is in contrast with RFC5452, which specifies that the query name is one of the attributes of a query that must be used to match a reply. This flaw could be abused to perform a DNS Cache Poisoning attack. If chained with CVE-2020-25684 the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity.

Severity

3.7 (Low)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

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{
  "affected": [],
  "aliases": [
    "CVE-2020-25685"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-326",
      "CWE-358"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-01-20T16:15:00Z",
    "severity": "MODERATE"
  },
  "details": "A flaw was found in dnsmasq before version 2.83. When getting a reply from a forwarded query, dnsmasq checks in forward.c:reply_query(), which is the forwarded query that matches the reply, by only using a weak hash of the query name. Due to the weak hash (CRC32 when dnsmasq is compiled without DNSSEC, SHA-1 when it is) this flaw allows an off-path attacker to find several different domains all having the same hash, substantially reducing the number of attempts they would have to perform to forge a reply and get it accepted by dnsmasq. This is in contrast with RFC5452, which specifies that the query name is one of the attributes of a query that must be used to match a reply. This flaw could be abused to perform a DNS Cache Poisoning attack. If chained with CVE-2020-25684 the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity.",
  "id": "GHSA-9gxq-wfg7-72x4",
  "modified": "2025-11-04T21:30:24Z",
  "published": "2022-05-24T17:39:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-25685"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1889688"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGB7HL3OWHTLEPSMLDGOMXQKG3KM2QME"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WYW3IR6APUSKOYKL5FT3ACTIHWHGQY32"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QGB7HL3OWHTLEPSMLDGOMXQKG3KM2QME"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WYW3IR6APUSKOYKL5FT3ACTIHWHGQY32"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/202101-17"
    },
    {
      "type": "WEB",
      "url": "https://www.arista.com/en/support/advisories-notices/security-advisories/12135-security-advisory-61"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2021/dsa-4844"
    },
    {
      "type": "WEB",
      "url": "https://www.jsof-tech.com/disclosures/dnspooq"
    },
    {
      "type": "WEB",
      "url": "https://www.kb.cert.org/vuls/id/434904"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2020-25685 (GCVE-0-2020-25685)

Vulnerability from cvelistv5 – Published: 2021-01-20 00:00 – Updated: 2025-11-04 19:12

Summary

Severity

No CVSS data available.

CWE

CWE-326

Assigner

redhat redhat root

References

8 references

URL	Tags
https://www.jsof-tech.com/disclosures/dnspooq/
https://bugzilla.redhat.com/show_bug.cgi?id=1889688
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisory
https://security.gentoo.org/glsa/202101-17	vendor-advisory
https://www.debian.org/security/2021/dsa-4844	vendor-advisory
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisory
https://www.arista.com/en/support/advisories-noti…
https://www.kb.cert.org/vuls/id/434904

Impacted products

1 product

Vendor	Product	Version
n/a	dnsmasq	Affected: dnsmasq 2.83

Show details on NVD website

JSON

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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.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.