The vulnerability is a stored cross‑site scripting flaw where a user who can create or edit an annotation guide can embed malicious Markdown that contains JavaScript. When another user loads that guide in the audio‑task view, the script runs inside the CVAT UI with the victim’s browser privileges, enabling the attacker to issue arbitrary CVAT requests that run with the victim’s authenticated session. The impact is thus the potential compromise of confidentiality, integrity, and availability through malicious client‑side code execution.

The flaw exists in CVAT versions 2.68.0 through 2.70.0, affecting the open‑source video and image annotation tool. The fix is available in release 2.70.0.

The CVSS base score of 8.5 indicates high severity. There is no EPSS data provided and the vulnerability is not listed in the CISA KEV catalog. Attackers need authenticated access that permits editing of annotation guides; therefore privilege is required to inject the payload. Once injected, the cross‑site scripting can be exploited by any user who subsequently opens the guide, making exploitation likely against users who interact with audio tasks. Given the high CVSS score and lack of mitigation, the risk is significant for impacted installations.