CVE-2026-21855 json
Tarkov Data Manager has Unauthenticated Reflected XSS
published 2026-01-07 10 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-1400
- cvss
- 9.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 15%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- tarkov tarkov_data_manager 2025-01-02
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 10 mo ago
Exploit prediction
0.24% chance of exploitation in the next 30 days, higher than 15% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/the-hideout/tarkov-data-manager/security/advisories/GHSA-9c23-rrg9-jc89 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N |
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
Affected products
- the-hideout tarkov-data-manager
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/the-hideout/tarkov-data-manager/security/advisories/GHSA-9c23-rrg9-jc89
exploit, vendor-advisory
Sources
- CVE List CVE-2026-21855
- NVD CVE-2026-21855
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.