{"cve":"CVE-2026-56864","nvd":{"published":"2026-08-13T22:17:22.677","modified":"2026-09-03T16:37:52.170","status":"Awaiting Analysis","description":"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_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","score":7.5},"cwes":["CWE-347"],"references":["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"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:48:17.459049833+00:00"},"epss":{"cve":"CVE-2026-56864","score":0.00298,"percentile":0.22508,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GO-2026-6180","url":"https://osv.dev/vulnerability/GO-2026-6180","summary":"Ignore unrelated, unauthenticated hashes in Lookup in golang.org/x/mod/sumdb","modified":"2026-08-19T12:25:49.995487491Z","packages":[{"ecosystem":"Go","name":"toolchain","purl":"pkg:golang/toolchain","ranges":["<1.25.13",">=1.26.0-0 <1.26.6",">=1.27.0-0 <1.27.0-rc.3"],"fixed":["1.25.13","1.26.6","1.27.0-rc.3"]},{"ecosystem":"Go","name":"golang.org/x/mod","purl":"pkg:golang/golang.org/x/mod","ranges":["<0.40.0"],"fixed":["0.40.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}