Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2026-05-11 05:44

Modified

2026-05-11 06:12

Summary

Crash when handling long CNAME response in net

Details

When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "golang",
        "purl": "pkg:bitnami/golang"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.25.10"
            },
            {
              "introduced": "1.26.0-0"
            },
            {
              "fixed": "1.26.3"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33811"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*"
    ],
    "severity": "High"
  },
  "details": "When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.",
  "id": "BIT-golang-2026-33811",
  "modified": "2026-05-11T06:12:18.508Z",
  "published": "2026-05-11T05:44:24.861Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://go.dev/cl/767860"
    },
    {
      "type": "WEB",
      "url": "https://go.dev/issue/78803"
    },
    {
      "type": "WEB",
      "url": "https://groups.google.com/g/golang-announce/c/qcCIEXso47M"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33811"
    },
    {
      "type": "WEB",
      "url": "https://pkg.go.dev/vuln/GO-2026-4981"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "Crash when handling long CNAME response in net"
}

CVE-2026-33811 (GCVE-0-2026-33811)

Vulnerability from cvelistv5 – Published: 2026-05-07 19:41 – Updated: 2026-05-08 14:25

Title

Crash when handling long CNAME response in net

Summary

When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.

Severity ?

7.5 (High)


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

CWE

CWE-415 - Double Free

Assigner

References

4 references

URL	Tags
https://go.dev/issue/78803
https://go.dev/cl/767860
https://groups.google.com/g/golang-announce/c/qcC…
https://pkg.go.dev/vuln/GO-2026-4981

Impacted products

1 product

Vendor	Product	Version
Go standard library	net	Affected: 0 , < 1.25.10 (semver) Affected: 1.26.0-0 , < 1.26.3 (semver)

Credits

hamayanhamayan

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "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"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-33811",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-08T14:25:39.702568Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-08T14:25:43.896Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "net",
          "product": "net",
          "programRoutines": [
            {
              "name": "cgoResSearch"
            },
            {
              "name": "LookupCNAME"
            },
            {
              "name": "Resolver.LookupCNAME"
            }
          ],
          "vendor": "Go standard library",
          "versions": [
            {
              "lessThan": "1.25.10",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.26.3",
              "status": "affected",
              "version": "1.26.0-0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "hamayanhamayan"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE-415: Double Free",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-07T19:41:19.285Z",
        "orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
        "shortName": "Go"
      },
      "references": [
        {
          "url": "https://go.dev/issue/78803"
        },
        {
          "url": "https://go.dev/cl/767860"
        },
        {
          "url": "https://groups.google.com/g/golang-announce/c/qcCIEXso47M"
        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2026-4981"
        }
      ],
      "title": "Crash when handling long CNAME response in net"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
    "assignerShortName": "Go",
    "cveId": "CVE-2026-33811",
    "datePublished": "2026-05-07T19:41:19.285Z",
    "dateReserved": "2026-03-23T20:35:32.814Z",
    "dateUpdated": "2026-05-08T14:25:43.896Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Action not permitted

Vulnerability from bitnami_vulndb

CVE-2026-33811 (GCVE-0-2026-33811)

Tags

Sightings

Nomenclature