{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-56864", "assignerOrgId": "1bb62c36-49e3-4200-9d77-64a1400537cc", "state": "PUBLISHED", "assignerShortName": "Go", "dateReserved": "2026-06-23T15:10:49.354Z", "datePublished": "2026-08-13T21:58:53.605Z", "dateUpdated": "2026-08-13T21:58:53.605Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc", "shortName": "Go", "dateUpdated": "2026-08-13T21:58:53.605Z"}, "title": "Ignore unrelated, unauthenticated hashes in Lookup in golang.org/x/mod/sumdb", "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/ && go mod tidy"}], "affected": [{"vendor": "Go toolchain", "product": "cmd/go", "collectionURL": "https://pkg.go.dev", "packageName": "cmd/go", "versions": [{"version": "0", "lessThan": "1.25.13", "status": "affected", "versionType": "semver"}, {"version": "1.26.0-0", "lessThan": "1.26.6", "status": "affected", "versionType": "semver"}, {"version": "1.27.0-0", "lessThan": "1.27.0-rc.3", "status": "affected", "versionType": "semver"}], "defaultStatus": "unaffected"}, {"vendor": "golang.org/x/mod", "product": "golang.org/x/mod/sumdb", "collectionURL": "https://pkg.go.dev", "packageName": "golang.org/x/mod/sumdb", "versions": [{"version": "0", "lessThan": "0.40.0", "status": "affected", "versionType": "semver"}], "programRoutines": [{"name": "Client.Lookup"}], "defaultStatus": "unaffected"}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "CWE-347: Improper Verification of Cryptographic Signature"}]}], "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"}], "credits": [{"lang": "en", "value": "mundur"}]}}}

{}

{"affected": [{"affectedData": [{"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"}]}], "source": "security@golang.org"}], "cveTags": [], "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/ && go mod tidy"}], "id": "CVE-2026-56864", "lastModified": "2026-08-13T22:17:22.677", "metrics": {}, "published": "2026-08-13T22:17:22.677", "references": [{"source": "security@golang.org", "url": "https://go.dev/cl/815000"}, {"source": "security@golang.org", "url": "https://go.dev/cl/815020"}, {"source": "security@golang.org", "url": "https://go.dev/issue/80745"}, {"source": "security@golang.org", "url": "https://groups.google.com/g/golang-announce/c/94pEornpRlI"}, {"source": "security@golang.org", "url": "https://pkg.go.dev/vuln/GO-2026-6180"}], "sourceIdentifier": "security@golang.org", "vulnStatus": "Received"}

{}

{}