SECURELYN

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 quer…

Scores

9.8
CVSS 9.8 out of 10, critical severity.
0.9%
EPSS 0.9% chance of exploitation in the next 30 days.

The facts

Published
13 October 2026
Last changed
16 October 2026
NVD status
Awaiting Analysis
Severity
Critical, CVSS 9.8 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.9% chance of exploitation activity in the next 30 days (percentile 59).

Is there a Securelyn advisory?

Not yet. Securelyn writes plain-English advisories for the flaws that matter most to businesses. Subscribe to the digest to hear about them.

References