CVE-2026-33540 — Server-Side Request Forgery in Distribution
Severity
7.5HIGHNVD
GHSA6.1OSV6.1
EPSS
0.0%
top 89.02%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedApr 6
Latest updateApr 13
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 configu…
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NExploitability: 3.9 | Impact: 3.6
Affected Packages4 packages
🔴Vulnerability Details
5VulDB▶
Distribution up to 3.0.x server-side request forgery (GHSA-3p65-76g6-3w7r / Nessus ID 305624)↗2026-04-13
OSV▶
CVE-2026-33540: Distribution is a toolkit to pack, ship, store, and deliver container content↗2026-04-07
OSV▶
Distribution affected by pull-through cache credential exfiltration via www-authenticate bearer realm↗2026-04-06
GHSA▶
Distribution affected by pull-through cache credential exfiltration via www-authenticate bearer realm↗2026-04-06
CVEList▶
Distribution affected by pull-through cache credential exfiltration via www-authenticate bearer realm↗2026-04-06
📋Vendor Advisories
1Red Hat▶
github.com/distribution/distribution: Distribution: Information disclosure via improper validation of authentication realm URL↗2026-04-06
🕵️Threat Intelligence
1💬Community
1Bugzilla▶
CVE-2026-33540 github.com/distribution/distribution: Distribution: Information disclosure via improper validation of authentication realm URL↗2026-04-06