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

Vulnerability from cvelistv5 – Published: 2026-08-13 21:58 – Updated: 2026-08-14 16:16
VLAI
Title
Ignore unrelated, unauthenticated hashes in Lookup in golang.org/x/mod/sumdb
Summary
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
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 CNA under the Google root
CNA scorecard E 42/100 over 76 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
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)
guessed Create a notification for this product.
golang.org/x/mod golang.org/x/mod/sumdb Affected: 0 , < 0.40.0 (semver)
guessed Create a notification for this product.
Credits
mundur
Show details on NVD website
To clipboard 

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      "title": "Ignore unrelated, unauthenticated hashes in Lookup in golang.org/x/mod/sumdb"
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}



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