CVE-2026-14574

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 36/100
Published: 2026-08-05 Modified: 2026-10-23 First seen: 2026-10-29 Status: active

Attack Surface

Low Complexity No Auth Integ. Impact

CVSS Vector Breakdown

AV: Local
AC: Low
PR: None
UI: Active
S: X
AT: Present
VC: Low
VI: High
VA: Low

Description

In Eclipse Theia versions 0.7.0 and up until including 1.73.1, the `PreferenceUtils.merge` function in `@theia/core` recursively merges preference values without rejecting prototype-related keys (`__proto__`, `constructor`, `prototype`). Because this function is invoked by `PreferenceServiceImpl.doResolve` for every preference resolution across scopes (default, user, workspace, folder), a crafted preference value in a workspace settings file (`.theia/settings.json` or `.vscode/settings.json`) can pollute `Object.prototype` when the user opens the workspace, potentially altering application logic across the Theia process.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
eclipse theia 0.7.0 – 1.74.0

Bug Bounty Relevance

36 / 100
✓ No authentication
✓ Low complexity

CVSS Score

5.7 / 10.0 v4.0
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:L/VI:H/VA:L/SC:N/SI:L/SA:L/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

EPSS — Exploitation Probability

0.40%
Raw Score 0.003950
Percentile 33.7%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00395
2026-10-28
0.00395

Intelligence Sources

nvd ref →