CVE-2026-100837

Contrast (Edgeless Systems) through 1.20.0 performs unanchored suffix matching when selecting per-registry configuration in the imagepuller. Config.registryFor strips a single trailing dot and then uses strings.HasSuffix(hostname, fqdn) without requiring a DNS label boundary, so a registry entry such as [registries."ghcr.io."] is also applied to any host whose name merely ends in that byte sequence, including attacker-registered domains such as evilghcr.io. When an image or layer is pulled from such a sibling domain, the imagepuller sends the configured Authorization header (basic auth, registry token, or identity token), trusts the configured custom CA bundle, follows the configured mirror, and honours insecure-skip-verify (disabling TLS verification) for that host. Image integrity is not affected, as image bytes remain pinned by digest in the policy and are validated after the pull. Configurations that use a leading dot (e.g., [registries.".example.registry"]) are unaffected.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/edgelesssys/contrast/security/advisories/GHSA-6c87-g9pw-78fx
https://www.vulncheck.com/advisories/edgeless-systems-contrast-through-1.20.0-credential-leak-via-registry-suffix-matching

Configurations

No configuration.

History

27 Sep 2026, 02:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-27 02:17

Updated : 2026-09-30 17:32

NVD link : CVE-2026-100837

Mitre link : CVE-2026-100837

CVE.ORG link : CVE-2026-100837

JSON object : View

Products Affected

No product.

CWE

CWE-1289

Improper Validation of Unsafe Equivalence in Input

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