CVE-2026-56864

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

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://go.dev/cl/815000
https://go.dev/cl/815020
https://go.dev/issue/80745
https://groups.google.com/g/golang-announce/c/94pEornpRlI
https://pkg.go.dev/vuln/GO-2026-6180

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-13 22:17

Updated : 2026-09-03 16:37

NVD link : CVE-2026-56864

Mitre link : CVE-2026-56864

CVE.ORG link : CVE-2026-56864

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

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