CVE-2026-105851

In Payload CMS versions before 3.90.0 and canary versions before 4.0.0-canary.34, local upload configurations that accept XML files can store an XML file and stylesheet that execute JavaScript in the Payload origin when a logged-in user opens the file. This leads to JavaScript execution in the victim's browser context.

In Payload CMS versions before 3.90.0 and canary versions before 4.0.0-canary.34, an authenticated user who can update or delete uploads stored locally can cause file cleanup to remove unintended files outside the configured upload directory, resulting in data loss or service disruption. Deployments that restrict upload management to trusted users are less exposed.

In Payload CMS versions before 3.90.0 and canary versions before 4.0.0-canary.34, a collection that allows downloadable SVG uploads can store a malicious SVG that bypasses sanitization and executes attacker-controlled JavaScript when a user downloads and opens the SVG. This leads to code execution in the victim's browser.

In Payload CMS versions after 3.0.0 and before 3.90.0, authenticated external URL-based upload retrieval can forward authentication data to a redirected destination that was not verified as trusted, potentially exposing a valid session to an unintended recipient. This issue is fixed in version 3.90.0.

Payload CMS in @payloadcms/plugin-mcp versions from 3.61.0 to 3.88.0 allows an authenticated user to manage MCP API keys outside the intended account, enabling privilege escalation through account takeover. This is fixed in version 3.88.0.

Payload CMS in versions after 3.0.0 and before 3.90.0 allows a custom field option that maps a field to a reserved authentication claim name to place unintended values in the authentication token issued at login. This issue is fixed in version 3.90.0.

Payload CMS before 3.90.0 and canary versions before 4.0.0-canary.34 has a vulnerability that allows an attacker to modify collection documents without enforcing collection or field-level access control when orderable is enabled. This issue is fixed in versions 3.90.0 and 4.0.0-canary.34.

Payload CMS in versions from 3.0.0 before 3.88.0 and canary versions before 4.0.0-canary.27 has a vulnerability that allows an untrusted user who can query readable collections through dynamic filters or joins to submit a request that causes SQL injection in the SQLite and Postgres adapters. This issue is fixed in versions 3.88.0 and 4.0.0-canary.27.

Payload CMS in versions from 3.0.0 before 3.88.0 and canary versions before 4.0.0-canary.27 has a vulnerability that allows an unauthenticated user to submit prototype-sensitive field paths when @payloadcms/plugin-import-export is enabled, causing unintended application behavior that can lead to remote code execution. This issue is fixed in versions 3.88.0 and 4.0.0-canary.27.

The @jhb.software/payload-alt-text-plugin version 0.7.0 for Payload CMS exposes POST /api/alt-text-plugin/generate and /bulk endpoints with a default guard accepting any authenticated user. The req.payload.findByID and req.payload.update calls do not set overrideAccess: false, so Payload defaults to skipping the collection's access functions. An authenticated low-privilege user can read protected documents and overwrite their alt and keywords fields.