CVE-2026-100838

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'.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

27 Sep 2026, 02:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-27 02:17

Updated : 2026-10-08 16:16

NVD link : CVE-2026-100838

Mitre link : CVE-2026-100838

CVE.ORG link : CVE-2026-100838

JSON object : View

Products Affected

No product.

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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