{"id":"CVE-2026-15788","state":"PUBLISHED","title":"WCOW cache mount source selector resolves NTFS junctions outside of cache root","description":"BuildKit's cache mount source= selector on Windows Container on Windows (WCOW) workers does not detect NTFS directory junctions placed inside the cache root. A build authored by an untrusted user on a WCOW-configured BuildKit daemon can read arbitrary host files reachable to the BuildKit daemon process.","publishedAt":"2026-07-20T19:12:56.386Z","updatedAt":"2026-07-21T12:40:56.055Z","severity":{"score":5.6,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","source":"Docker"},"assigner":"Docker","products":["moby BuildKit"],"affected":[{"vendor":"moby","product":"BuildKit","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"0.31.2","versionType":"semver"}],"platforms":["Windows"]}],"references":["https://github.com/moby/buildkit/security/advisories/GHSA-388v-wmr2-g2v2"],"weaknesses":["CWE-59"],"ingestedAt":"2026-10-29T20:11:00.674Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/15xxx/CVE-2026-15788.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-15788","state":"PUBLISHED","datePublished":"2026-07-20T19:12:56.386Z","dateUpdated":"2026-07-21T12:40:56.055Z","assignerShortName":"Docker","assignerOrgId":"686469e6-3ff6-451b-ab8b-cf5b9e89401e","dateReserved":"2026-07-14T19:25:38.521Z"},"containers":{"cna":{"title":"WCOW cache mount source selector resolves NTFS junctions outside of cache root","descriptions":[{"lang":"en","value":"BuildKit's cache mount source= selector on Windows Container on Windows (WCOW) workers does not detect NTFS directory junctions placed inside the cache root. A build authored by an untrusted user on a WCOW-configured BuildKit daemon can read arbitrary host files reachable to the BuildKit daemon process."}],"affected":[{"vendor":"moby","product":"BuildKit","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"0.31.2","versionType":"semver"}],"platforms":["Windows"]}],"references":[{"url":"https://github.com/moby/buildkit/security/advisories/GHSA-388v-wmr2-g2v2","tags":["vendor-advisory"]}],"metrics":[{"cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","baseScore":5.6,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"ACTIVE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","exploitMaturity":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-59","description":"CWE-59: Improper Link Resolution Before File Access ('Link Following')","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"Docker","orgId":"686469e6-3ff6-451b-ab8b-cf5b9e89401e","dateUpdated":"2026-07-20T19:12:56.386Z"},"credits":[{"lang":"en","type":"finder","value":"Junyi Liu (mosskappa)"}],"impacts":[{"capecId":"CAPEC-132","descriptions":[{"lang":"en","value":"CAPEC-132 Symlink Attack"}]}],"source":{"discovery":"EXTERNAL"},"workarounds":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"Use trusted build sources."}],"value":"Use trusted build sources."}]},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-21T12:40:15.680950Z","id":"CVE-2026-15788","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-21T12:40:56.055Z"}}]}}}