{"id":"CVE-2026-39822","sourceIdentifier":"security@golang.org","published":"2026-07-08T17:17:21.310","lastModified":"2026-09-17T17:10:20.047","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"On Unix systems, opening a file in an os.Root improperly follows symlinks to locations outside of the Root when the final path component of the a path is a symbolic link and the path ends in /. For example, 'root.Open(\"symlink/\")' will open \"symlink\" even when \"symlink\" is a symbolic link pointing outside of the root."}],"affected":[{"source":"security@golang.org","affectedData":[{"vendor":"Go standard library","product":"os","defaultStatus":"unaffected","collectionURL":"https://pkg.go.dev","packageName":"os","programRoutines":[{"name":"rootOpenFileNolog"},{"name":"openRootInRoot"},{"name":"OpenInRoot"},{"name":"Root.Create"},{"name":"Root.Open"},{"name":"Root.OpenFile"},{"name":"Root.OpenRoot"},{"name":"Root.ReadFile"},{"name":"Root.WriteFile"},{"name":"rootFS.Open"},{"name":"rootFS.ReadDir"},{"name":"rootFS.ReadFile"}],"versions":[{"version":"0","lessThan":"1.25.12","versionType":"semver","status":"affected"},{"version":"1.26.0-0","lessThan":"1.26.5","versionType":"semver","status":"affected"},{"version":"1.27.0-0","lessThan":"1.27.0-rc.2","versionType":"semver","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-07-08T18:06:16.360721Z","id":"CVE-2026-39822","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary","description":[{"lang":"en","value":"CWE-61"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*","versionStartIncluding":"1.24.0","versionEndExcluding":"1.25.12","matchCriteriaId":"4E50284C-BE19-4F62-ABAE-B78B6BECDF49"},{"vulnerable":true,"criteria":"cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*","versionStartIncluding":"1.26.0","versionEndExcluding":"1.26.5","matchCriteriaId":"08CDCAED-0C22-42D9-97A8-77F19DEECDB2"},{"vulnerable":true,"criteria":"cpe:2.3:a:golang:go:1.27:rc1:*:*:*:*:*:*","matchCriteriaId":"1062DCC7-46FE-4CF5-ADEF-BEC03F8AB39E"}]}]}],"references":[{"url":"https://go.dev/cl/797880","source":"security@golang.org","tags":["Patch"]},{"url":"https://go.dev/issue/79005","source":"security@golang.org","tags":["Issue Tracking","Patch"]},{"url":"https://groups.google.com/g/golang-announce/c/OrmQE_Yp5Sc","source":"security@golang.org","tags":["Mailing List","Patch","Vendor Advisory"]},{"url":"https://pkg.go.dev/vuln/GO-2026-4970","source":"security@golang.org","tags":["Vendor Advisory"]}]}