Prototype Pollution in Jetbrains Youtrack

CVE-2026-57926

In JetBrains YouTrack before 2026.2.16593 the websandbox bridge was vulnerable to a prototype pollution attack

Vulnerability class: Prototype Pollution

Published · last modified .

CVSS v3 metric

CVSS v3 base score 2.6 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (24.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 24.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-57926: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-57926?
CVE-2026-57926 is a low-severity vulnerability in Jetbrains Youtrack, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). CVSS score: 2.6/10. Published 2026-06-26.
How severe is CVE-2026-57926?
Low severity. CVSS v3 base score is 2.6 out of 10.