CVE-2024-39897 Cache driver GetBlob() allows read access to any blob without access control check

2024-07-0918:48:24

CWE-639

GitHub_M

www.cve.org

cache driver

getblob

read access

access control

zot

oci image registry

dedupe

vulnerability

fix

cve-2024-39897

CVSS3

4.3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

LOW

Integrity Impact

NONE

Availability Impact

NONE

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

EPSS

Percentile

9.2%

JSON

zot is an OCI image registry. Prior to 2.1.0, the cache driver GetBlob() allows read access to any blob without access control check. If a Zot accessControl policy allows users read access to some repositories but restricts read access to other repositories and dedupe is enabled (it is enabled by default), then an attacker who knows the name of an image and the digest of a blob (that they do not have read access to), they may maliciously read it via a second repository they do have read access to.
This attack is possible because ImageStore.CheckBlob() calls checkCacheBlob() to find the blob a global cache by searching for the digest. If it is found, it is copied to the user requested repository with copyBlob(). The attack may be mitigated by configuring “dedupe”: false in the “storage” settings. The vulnerability is fixed in 2.1.0.

CNA Affected

[
  {
    "vendor": "project-zot",
    "product": "zot",
    "versions": [
      {
        "version": "< 2.1.0",
        "status": "affected"
      }
    ]
  }
]