CVAT has stored XSS via annotation guide assets

published 2026-08-04 3 mo ago modified 2026-10-24 15 d ago also EUVD-2026-52895

cvss: 8.5; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 35%
public exploits: 0; none known

CVAT is an open source interactive video and image annotation tool for computer vision. Versions 2.5.0 through 2.66.0 contain a XSS vulnerability that can be accessed through annotation guide assets. When CVAT serves the files attached to an annotation guide, it labels them with a media type ( Content-Type ) that the attacker can influence, so instead of treating an uploaded file as plain data, the victim's browser can be told to treat it as an HTML page and run any JavaScript inside it. This issue has been fixed in version 2.67.0.

Patch / fix

fixed in 2 links 1

cvat computer_vision_annotation_tool 2.67.0
cvat cvat 2.67.0

github.com/cvat-ai/cvat@44d717a commit

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 3 mo ago (2026-08-05)

Exploit prediction

0.40% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.5	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
CNA	4.0	8.5	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

cvat-ai cvat

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation
CWE-434 Unrestricted Upload of File with Dangerous Type

References

Sources

CVE List CVE-2026-65986
NVD CVE-2026-65986

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary