CVE-2026-33540

HIGH EPSS 19.1%
Published Apr 6, 20262mo ago · Modified Jun 17, 20262w ago
7.5 CVSS 3.1
High
Find Similar
Published Apr 6, 2026 2mo ago
Last Modified Jun 17, 2026 2w ago

Description

Distribution is a toolkit to pack, ship, store, and deliver container content. Prior to 3.1.0, in pull-through cache mode, distribution discovers token auth endpoints by parsing WWW-Authenticate challenges returned by the configured upstream registry. The realm URL from a bearer challenge is used without validating that it matches the upstream registry host. As a result, an attacker-controlled upstream (or an attacker with MitM position to the upstream) can cause distribution to send the configured upstream credentials via basic auth to an attacker-controlled realm URL. This vulnerability is fixed in 3.1.0.

CVSS Details

Base Score
7.5
Exploitability
3.9
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity None
Availability None

Threat Intelligence

EPSS Exploit Probability
19.1% percentile
Exploit & Patch Status
Public Exploit Known
No Patch Available

Weaknesses 1

CWE-918 Server-Side Request Forgery (SSRF) Validation

Affected Products 1

VendorProductVersionRange
distribution_projectdistribution* <3.1.0

References 1

  • github.com https://github.com/distribution/distribution/security/advisories/GHSA-3p65-76g6-3w7r
    ExploitMitigationVendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.