XSS in Tarkov Data Manager
CVE-2026-21855
The Tarkov Data Manager is a tool to manage the Tarkov item data. Prior to 02 January 2025, a reflected Cross Site Scripting (XSS) vulnerability in the toast notification system allows any attacker to execute arbitrary JavaScript in the context of a victim's browser session by crafting a malicious URL. A series of fix commits on 02 January 2025 fixed this and other vulnerabilities.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.3 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.002 (13.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 13th percentile — 13.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
- Tarkov Data Manager
- The-Hideout Tarkov-Data-Manager — versions <= 2.0.0
Weakness classification (CWE)
References
- github.com/the-hideout/tarkov-data-manager/security/advisories/GHSA-9c23-rrg9-j… (Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-21855?
- CVE-2026-21855 is a critical-severity vulnerability in Tarkov Data Manager, classified under Cross-site Scripting. CVSS score: 9.3/10. Published 2026-01-07.
- How severe is CVE-2026-21855?
- Critical severity. CVSS v3 base score is 9.3 out of 10.