← Vulnerability feed

Vulnerability record · CVE-2026-33540 · published 6 April 2026

CVE-2026-33540: Distribution project distribution server-side request forgery (ssrf) vulnerability

Distribution Project · Distribution

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.

7.5 CVSS 3.1 High EPSS 0.39% · top 69.6% CWE-918 · Server-side request forgery (SSRF)
7.5CVSS 3.1 base score
0.39%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References, 2 tagged exploit
17 Jun 2026Last modified by NVD

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

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

Track CVE-2026-33540 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

10.0CVE-2026-83548SonicWall SMA1000 pre-auth SSRF via alternate access pathThe SMA1000 Appliance Work Place interface exposes an unintended alternate access path that allows server-side request forgery before authentication.…KEVEPSS 8.8%analysed10.0CVE-2026-49869Kestra OSS auth bypass via path suffix match enables RCEKestra OSS AuthenticationFilter whitelists the public config endpoint using request.getPath().endsWith("/configs"), a suffix match instead of an exac…KEVEPSS 2.1%analysed9.3CVE-2026-64849MLflow unauthenticated webhook test endpoint SSRF via redirectMLflow before 3.15.0 validates the webhook URL only on the original request, while the delivery code follows redirects and re-resolves the hostname w…KEVEPSS 9.8%analysed10.0CVE-2026-15409SonicWall SMA1000 Work Place SSRF allows unauthenticated requestsThe SMA1000 Appliance Work Place interface contains a server-side request forgery flaw (CWE-918) that lets the appliance be induced to make requests …KEVEPSS 6.8%analysed8.6CVE-2026-20230Cisco Unified CM SSRF enables file write and root escalationCisco Unified Communications Manager and Unified CM SME fail to properly validate input for specific HTTP requests, allowing server-side request forg…KEVEPSS 88%analysed7.5CVE-2021-22054VMware Workspace ONE UEM console unauthenticated SSRFThe Workspace ONE UEM console contains a server-side request forgery flaw in versions 20.0.8 before 20.0.8.37, 20.11.0 before 20.11.0.40, 21.2.0 befo…KEVEPSS 100%analysed9.8CVE-2021-22175GitLab unauthenticated SSRF via internal webhook requestsGitLab is vulnerable to server-side request forgery when requests to the internal network for webhooks are enabled. The flaw affects all versions sta…KEVEPSS 53%analysed9.8CVE-2020-7796Zimbra Collaboration Suite WebEx zimlet SSRFZimbra Collaboration Suite before 8.8.15 Patch 7 is vulnerable to server-side request forgery when the WebEx zimlet is installed and its JSP is enabl…KEVEPSS 84%analysed

Source: NIST National Vulnerability Database (record CVE-2026-33540), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.