Sources: National Vulnerability Database, CVE.org, CISA KEV, FIRST EPSS
CVE-2026-125358 Overview
Universal-modder before commit e88f6876745427321eb755ebc98276063a962d8a contains a missing WebSocket Origin validation vulnerability in the HostLink class of its passthrough example mods that allows remote attackers to execute Minecraft commands. Any web page open in the player's browser can connect cross-site to the unauthenticated loopback WebSocket and send cmd messages that WorldBridge.command() runs with operator authority.
Critical Impact
Affected Products
- HostLink class of its passthrough example mods that: see the vendor advisory for the exact affected versions
Discovery Timeline
- 2026-11-10: CVE-2026-125358 published to the National Vulnerability Database by disclosure@vulncheck.com
- 2026-11-10: last updated in the NVD database
Technical Details for CVE-2026-125358
Vulnerability Analysis
CVE-2026-125358 is a Security Vulnerability weakness (CWE-1385) in HostLink class of its passthrough example mods that. Based on its CVSS vector, the flaw can be reached over the network, needs no login, and relies on a user taking an action.
With a CVSS base score of 7.2, apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Root Cause
The vendor description states: Universal-modder before commit e88f6876745427321eb755ebc98276063a962d8a contains a missing WebSocket Origin validation vulnerability in the HostLink class of its passthrough example mods that allows remote attackers to execute Minecraft commands. Any web page open in the player's browser can connect cross-site to the unauthenticated loopback WebSocket and send cmd messages that WorldBridge.command() runs with operator authority.
Attack Vector
Based on the CVSS vector, the flaw can be reached over the network, needs no login, and relies on a user taking an action. Attack complexity is low complexity.
No exploitation in the wild is confirmed by CISA at the time of the last update. Check the references below for any vendor or researcher proof of concept.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/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
Detection Methods for CVE-2026-125358
Detection Strategies
- Inventory every instance of HostLink class of its passthrough example mods that and compare the running version with the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Run an authenticated vulnerability scan once your scanner ships a check for this CVE.
Monitoring Recommendations
- Forward HostLink class of its passthrough example mods that application, access and audit logs to your SIEM for retrospective hunting.
- Alert on new processes, configuration changes or outbound connections from the affected service.
- Track the vendor advisory and the CISA KEV catalog for changes in exploitation status.
How to Mitigate CVE-2026-125358
Immediate Actions Required
- Apply the fixed version of HostLink class of its passthrough example mods that named in the vendor advisory.
- Prioritize internet facing and business critical instances first.
- Rescan after the change to confirm the exposure is closed.
Patch Information
Use the fixed version listed in the vendor advisory for HostLink class of its passthrough example mods that.
Workarounds
- If patching must wait, restrict network access to the affected service and place it behind authentication or a web application firewall rule.
CWE References
Technical References
This entry is built directly from NVD, CISA KEV and EPSS data. Verify fixed versions in the vendor advisory before you deploy.
Frequently asked questions
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