CVE-2026-104252

Vitess is a database clustering system for horizontal scaling of MySQL. Prior to 23.0.5 and 24.0.2, twopczHandler in go/vt/vttablet/tabletserver/twopcz.go writes the Action and dtid form values from the vttablet and vtcombo /twopcz HTTP debug endpoint into a text/html response without HTML escaping. Under the default allow-all ACL policy, a remote unauthenticated attacker can send an operator a crafted request that executes script in the operator's browser after the request is opened. The script runs with the vttablet debug origin and can read same-origin diagnostic endpoints that expose query, transaction, environment, variable, or profiling data available in that deployment. This issue is fixed in versions 23.0.5 and 24.0.2.

The risk includes execution of malicious script in the operator's browser, potentially leading to exposure of sensitive diagnostic data, including queries, transactions, and environment data, and potentially further attacks.

It is recommended to immediately update Vitess to version 23.0.5 or 24.0.2 and restrict access to the /twopcz debug endpoints.