{"id":"CVE-2026-100838","state":"PUBLISHED","title":"Contrast before 1.19.1 CopyFile Policy Symlink Subversion","description":"Contrast is a confidential-computing runtime for Kubernetes. In versions before 1.19.1, the Kata agent policies generated by the Contrast CLI contained a flaw in the CopyFile verification that allowed arbitrary writes to the guest root filesystem. A malicious process on the untrusted host able to connect to the Kata agent VSOCK could issue a series of CopyFile requests to overwrite security-critical files in the guest or trick the workload into disclosing sensitive data, effectively amounting to a full guest takeover. Users unable to upgrade can apply an equivalent rego policy fix passed to 'contrast generate --policy'.","publishedAt":"2026-09-27T01:28:35.498Z","updatedAt":"2026-10-08T15:22:00.652Z","severity":{"score":8.6,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["edgelesssys contrast"],"affected":[{"vendor":"edgelesssys","product":"contrast","packageURL":"pkg:golang/github.com/edgelesssys/contrast","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"1.19.1","versionType":"semver"},{"version":"1.19.1","status":"unaffected","versionType":"semver"}]}],"references":["https://github.com/edgelesssys/contrast/security/advisories/GHSA-rh99-wc69-c255","https://www.vulncheck.com/advisories/contrast-before-1.19.1-copyfile-policy-symlink-subversion"],"weaknesses":["CWE-59"],"ingestedAt":"2026-10-29T20:10:13.529Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/100xxx/CVE-2026-100838.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-100838","state":"PUBLISHED","datePublished":"2026-09-27T01:28:35.498Z","dateUpdated":"2026-10-08T15:22:00.652Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-09-26T23:23:03.411Z"},"containers":{"cna":{"title":"Contrast before 1.19.1 CopyFile Policy Symlink Subversion","descriptions":[{"lang":"en","value":"Contrast is a confidential-computing runtime for Kubernetes. 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