Pelican Web UI Affected by a Privilege Escalation Attack
Date: 2026-05
Affected: go/github.com/pelicanplatform/pelican
Attack vector: auth-bypass
Category: vulnerability-disclosure
Severity: Critical
CVE: CVE-2026-42571
CWE: CWE-863

## Background On April 2nd, 2026, a Claude coding agent alerted Pelican PI Brian Bockelman to a privilege escalation vulnerability affecting Pelican's Web User Interface (WebUI) for various versions between `v7.21` and `v7.24`. Upon further investigation, the Pelican team discovered this attack allows any user authenticated to the WebUI via OAuth to gain admin privileges under certain configurations. These may include servers with the following configuration variables enabled: - **Server.UIAdminUsers**: Affected if any of the listed admin users or the default admin account have not previously logged in to the server. - **Server.AdminGroups**: Affected if `Issuer.GroupSource` is set to `internal` and an admin of the group has not previously logged in to the server. The OSDF operations team has mitigated these for core services, origins, and caches operated by the PATh project. However, mitigation may be needed for caches and origins not centrally operated. **Pelican Command Line has not currently identified any evidence this attack has been exploited in the services managed by OSDF operators.** ## Severity and Impact When leveraged, an attacker with any kind of authenticated session on the server can create database records that cause the server to grant them admin privileges on subsequent login. Critically, admin access enables modifying the server's configuration, creating persistent API tokens, and changing admin passwords. The table below summarizes potential impli


Mitigations:

Architectural layers (MAESTRO):