CVE-2026-16492

Postiz signs its session, invitation and password reset tokens with one shared secret and without any marker of what a token is for. A route that refreshes the credentials of a browser-extension channel signed data taken from the request itself and stored the result where the requesting user can read it back, allowing a user to obtain a validly signed token containing any claims they choose, accepted as a session, an organization invitation with a chosen role, a password reset or an enterprise provisioning token.

Python has added a denylist for known compromised certificates to the "ssl" module to ensure user safety even without certificate revocation configured. Known compromised certificates will automatically be rejected regardless of the SSLContext policy configuration.

In Postiz, a media path that is not a web address is treated as a file on the server's disk without verifying it lies inside the upload directory. A registered user can store a crafted media path with a post and cause the publishing worker to read an arbitrary file and send it as an attachment to a Discord server the user controls. The same unconfined reads are reachable through two further routes, including file existence checks and backend memory exhaustion; self-registration is open by default.

The WordPress plugin Newsletters (newsletters-lite) up to version 4.18.1 contains a deserialization of untrusted data vulnerability, allowing object injection. This could enable an attacker to execute unintended code.

The WordPress plugin Paytium up to version 5.0.5 is vulnerable to deserialization of untrusted data, allowing object injection. This may enable an attacker to perform unauthorized actions.

The WordPress plugin Product Filter by WBW (woo-product-filter) up to version 3.4.6 is vulnerable to blind SQL injection due to improper neutralization of special elements in SQL commands. An attacker could exploit this to manipulate database queries.

The WordPress plugin Newsletters (newsletters-lite) up to version 4.18.1 is vulnerable to SQL injection due to improper neutralization of special elements in SQL commands. This could allow an attacker to execute arbitrary SQL queries.

The asVereinbase WordPress plugin before version 1.1.8 does not require a valid password or a genuine second factor before authenticating a user, treating an empty stored value as a match. This allows an unauthenticated attacker to log in as any user, including an administrator.

The Prime Mover – Backup and Migration plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 2.2.1 via deserialization of untrusted input in the migration search-and-replace routine. An unauthenticated attacker can store a crafted, base64-encoded serialized object in wp_comments.comment_content through the standard comment-submission endpoint. When an administrator performs a routine export or restore, the plugin base64-decodes that stored value and passes it to unserialize() with no allowed_classes restriction. A Property-Oriented Programming (POP) chain is present in the plugin's own bundled Freemius library, so no additional plugin or theme is required.

Postiz lets a signed-in user ask the backend to run a function on one of their connected channels, but the backend did not restrict which functions could be requested, allowing calls to internal helpers. One helper reads a file from the server's disk (e.g., environment file with the session signing secret, database address, and service credentials), and another makes the backend process exit with a single request. Self-registration is open by default, so no existing account or action by another user is needed.