A malicious GOPROXY was previously capable of forging up to two sumdb tiles that allow for a requested module to bypass the GOSUMDB check and persist attacker-controlled module content to a local Go module cache. This attack allows for a malicious GOPROXY to serve malicious module content that cannot be detected by evaluating the transparency log. All tiles are now correctly verified against their parents. In order to determine if you have been affected: rm -r go.sum go.work.sum vendor/ && go mod tidy
Metrics
Affected Vendors & Products
References
History
Fri, 14 Aug 2026 16:30:00 +0000
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| Metrics |
cvssV3_1
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Fri, 14 Aug 2026 13:00:00 +0000
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| First Time appeared |
Golang
Golang mod Gotoolchain Gotoolchain cmd/go |
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| Vendors & Products |
Golang
Golang mod Gotoolchain Gotoolchain cmd/go |
Fri, 14 Aug 2026 01:15:00 +0000
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| Weaknesses | CWE-347 |
Thu, 13 Aug 2026 22:15:00 +0000
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| Description | A malicious GOPROXY was previously capable of forging up to two sumdb tiles that allow for a requested module to bypass the GOSUMDB check and persist attacker-controlled module content to a local Go module cache. This attack allows for a malicious GOPROXY to serve malicious module content that cannot be detected by evaluating the transparency log. All tiles are now correctly verified against their parents. In order to determine if you have been affected: rm -r go.sum go.work.sum vendor/ && go mod tidy | |
| Title | Fix transparency log tile verification bypass in golang.org/x/mod/sumdb/tlog | |
| References |
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Status: PUBLISHED
Assigner: Go
Published:
Updated: 2026-08-14T15:34:17.235Z
Reserved: 2026-06-23T15:10:49.354Z
Link: CVE-2026-56865
Updated: 2026-08-14T15:34:11.473Z
Status : Received
Published: 2026-08-13T22:17:22.797
Modified: 2026-08-14T16:16:57.860
Link: CVE-2026-56865
No data.
OpenCVE Enrichment
Updated: 2026-08-14T12:14:26Z