{"id":"CVE-2026-100838","summary":"Contrast before 1.19.1 CopyFile Policy Symlink Subversion","details":"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'.","aliases":["GHSA-rh99-wc69-c255","GO-2026-5624"],"modified":"2026-09-28T03:48:30.954855648Z","published":"2026-09-27T01:28:35.498Z","database_specific":{"cna_assigner":"VulnCheck","cwe_ids":["CWE-59"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/100xxx/CVE-2026-100838.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/100xxx/CVE-2026-100838.json"},{"type":"ADVISORY","url":"https://github.com/edgelesssys/contrast/security/advisories/GHSA-rh99-wc69-c255"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-100838"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/contrast-before-1.19.1-copyfile-policy-symlink-subversion"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/edgelesssys/contrast","events":[{"introduced":"0"},{"fixed":"2a5f2b256d9b0d8517d4653ed4e8bd7d39fb44f3"}],"database_specific":{"source":["AFFECTED_FIELD","DESCRIPTION"],"extracted_events":[{"introduced":"0"},{"fixed":"1.19.1"}]}}],"versions":["v1.19.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-100838.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"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"}]}