Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2026-08-19 11:37

Modified

2026-08-19 12:00

Summary

Ignore unrelated, unauthenticated hashes in Lookup in golang.org/x/mod/sumdb

Details

A malicious GOSUMDB was capable of serving arbitrary module content not contained within the transparency log. This attack allows for a coordinating GOPROXY and GOSUMDB to serve a client malicious module content that cannot be detected by evaluating the transparency log. In order to determine if you have been affected: rm -r go.sum go.work.sum vendor/ && go mod tidy

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "golang",
        "purl": "pkg:bitnami/golang"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.25.13"
            },
            {
              "introduced": "1.26.0-0"
            },
            {
              "fixed": "1.26.6"
            },
            {
              "introduced": "1.27.0-0"
            },
            {
              "fixed": "1.27.0"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-56864"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*"
    ],
    "severity": "High"
  },
  "details": "A malicious GOSUMDB was capable of serving arbitrary module content not contained within the transparency log. This attack allows for a coordinating GOPROXY and GOSUMDB to serve a client malicious module content that cannot be detected by evaluating the transparency log. In order to determine if you have been affected: rm -r go.sum go.work.sum vendor/ \u0026\u0026 go mod tidy",
  "id": "BIT-golang-2026-56864",
  "modified": "2026-08-19T12:00:51.730Z",
  "published": "2026-08-19T11:37:52.101Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://go.dev/cl/815000"
    },
    {
      "type": "WEB",
      "url": "https://go.dev/cl/815020"
    },
    {
      "type": "WEB",
      "url": "https://go.dev/issue/80745"
    },
    {
      "type": "WEB",
      "url": "https://groups.google.com/g/golang-announce/c/94pEornpRlI"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56864"
    },
    {
      "type": "WEB",
      "url": "https://pkg.go.dev/vuln/GO-2026-6180"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "Ignore unrelated, unauthenticated hashes in Lookup in golang.org/x/mod/sumdb"
}

CVE-2026-56864 (GCVE-0-2026-56864)

Vulnerability from cvelistv5 – Published: 2026-08-13 21:58 – Updated: 2026-08-14 16:16

Title

Ignore unrelated, unauthenticated hashes in Lookup in golang.org/x/mod/sumdb

Summary

Severity

7.5 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-14 16:16 UTC

CWE

CWE-347 - Improper Verification of Cryptographic Signature

Assigner

Go Google root

References

5 references

URL	Tags
https://go.dev/issue/80745
https://groups.google.com/g/golang-announce/c/94p…
https://go.dev/cl/815000
https://go.dev/cl/815020
https://pkg.go.dev/vuln/GO-2026-6180

Impacted products

2 products

Vendor	Product	Version
Go toolchain	cmd/go	Affected: 0 , < 1.25.13 (semver) Affected: 1.26.0-0 , < 1.26.6 (semver) Affected: 1.27.0-0 , < 1.27.0-rc.3 (semver)
golang.org/x/mod	golang.org/x/mod/sumdb	Affected: 0 , < 0.40.0 (semver)

Credits

mundur

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 7.5,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-56864",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-14T16:16:37.911009Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-347",
                "description": "CWE-347 Improper Verification of Cryptographic Signature",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-14T16:16:42.248Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "cmd/go",
          "product": "cmd/go",
          "vendor": "Go toolchain",
          "versions": [
            {
              "lessThan": "1.25.13",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.26.6",
              "status": "affected",
              "version": "1.26.0-0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.27.0-rc.3",
              "status": "affected",
              "version": "1.27.0-0",
              "versionType": "semver"
            }
          ]
        },
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "golang.org/x/mod/sumdb",
          "product": "golang.org/x/mod/sumdb",
          "programRoutines": [
            {
              "name": "Client.Lookup"
            }
          ],
          "vendor": "golang.org/x/mod",
          "versions": [
            {
              "lessThan": "0.40.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "mundur"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "A malicious GOSUMDB was capable of serving arbitrary module content not contained within the transparency log. This attack allows for a coordinating GOPROXY and GOSUMDB to serve a client malicious module content that cannot be detected by evaluating the transparency log. In order to determine if you have been affected:   rm -r go.sum go.work.sum vendor/ \u0026\u0026 go mod tidy"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE-347: Improper Verification of Cryptographic Signature",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-13T21:58:53.605Z",
        "orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
        "shortName": "Go"
      },
      "references": [
        {
          "url": "https://go.dev/issue/80745"
        },
        {
          "url": "https://groups.google.com/g/golang-announce/c/94pEornpRlI"
        },
        {
          "url": "https://go.dev/cl/815000"
        },
        {
          "url": "https://go.dev/cl/815020"
        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2026-6180"
        }
      ],
      "title": "Ignore unrelated, unauthenticated hashes in Lookup in golang.org/x/mod/sumdb"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
    "assignerShortName": "Go",
    "cveId": "CVE-2026-56864",
    "datePublished": "2026-08-13T21:58:53.605Z",
    "dateReserved": "2026-06-23T15:10:49.354Z",
    "dateUpdated": "2026-08-14T16:16:42.248Z",
    "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.

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.