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Fencer Intel
critical 9.8

CVE-2026-21854 json

Tarkov Data Manager Authentication Bypass vulnerability

published 10mo ago modified 4mo ago also EUVD-2026-1399

cvss
9.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 40%
public exploits
0
none known

Summary

The Tarkov Data Manager is a tool to manage the Tarkov item data. Prior to 02 January 2025, an authentication bypass vulnerability in the login endpoint allows any unauthenticated user to gain full admin access to the Tarkov Data Manager admin panel by exploiting a JavaScript prototype property access vulnerability, combined with loose equality type coercion. A series of fix commits on 02 January 2025 fixed this and other vulnerabilities.

Patch / fix

  • tarkov tarkov_data_manager 2025-01-02

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
total
Assessed
10mo ago

Exploit prediction

0.46% chance of exploitation in the next 30 days, higher than 40% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

  • the-hideout tarkov-data-manager

Classification

Weakness
  • CWE-287 Improper Authentication
  • CWE-843 Access of Resource Using Incompatible Type
  • CWE-1321 Improperly Controlled Modification of Object Prototype Attributes

References

Sources

Fencer Intel 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.