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TI-2026-08811 Aliases CVE-2026-10054

Missing authentication in Eclipse Theia

Priority LOW 39CWE-1385Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-306.

Summary

In affected versions of Eclipse Theia (1.8.1 and later), the browser backend exposes privileged terminal RPC over WebSocket (/services/shell-terminal, /services/terminals/:id) without service-level authentication. WebSocket origin validation in @theia/core is fail-open: connections are accepted when the Origin header is missing or when no THEIA_HOSTS allowlist is configured (the default). The Socket.IO integration additionally replaces the real Origin header with a client-supplied fix-origin header that an attacker can control or omit. As a result, a foreign-origin web page visited by a user with a running Theia instance can open the /services WebSocket namespace, invoke terminal creation, attach to the resulting terminal data channel, execute arbitrary OS commands, and read their output. This affects both local developer setups (drive-by attack) and hosted or tunneled deployments without strong external authentication. A fix is in development that enforces same-origin validation by default, removes trust in the fix-origin header, gates HTTP and WebSocket access on a SameSite=Strict; HttpOnly connection-token cookie, and sanitizes shell terminal creation options.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00219 12th percentileScored 2026-11-07
Fix Fixed Eclipse Theia (Eclipse Foundation): 1.73.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Eclipse FoundationEclipse Theia1.8.1 to before 1.73.01.73.0Patch availableCNA
  • Eclipse Theia VendorEclipse Foundation Affected 1.8.1 to before 1.73.0 Fixed in 1.73.0 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:eclipse:theia:*:*:*:*:*:*:*:*——Eclipse Foundation

Remediation

  • Fix · CNA Eclipse Theia (Eclipse Foundation) Fixed in 1.73.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Eclipse Theia 1.73.0

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2026-08812 Information disclosure in Eclipse TheiaPriority LOW 37
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-10054

References

Other 2

  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2026-81947 Unauthenticated command injection in Eclipse Che che-machine-exec CVSS 3.1CRITICAL 9.8
  • TI-2026-13216 CWE-863: ABAC authorization bypass via trailing slash route normalization in Eclipse BaSyx Go Components CVSS 3.1CRITICAL 9.8
  • TI-2026-06514 Path traversal in Eclipse BaSyx CVSS 3.1CRITICAL 10.0
  • TI-2026-01382 In the Eclipse Theia Website repository, the GitHub Actions workflow… CVSS 3.1CRITICAL 10.0
  • TI-2026-74697 Authentication bypass in Eclipse Jetty EthereumAuthenticator CVSS 4.0CRITICAL 9.3
See all 466 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences