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2 vulnerabilities found for Eclipse Langium by Eclipse Foundation
CVE-2026-124683 (GCVE-0-2026-124683)
Vulnerability from cvelistv5 – Published: 2026-11-09 16:02 – Updated: 2026-11-09 16:47
VLAI
EPSS
VEX
Summary
Eclipse Langium versions 3.2.0 through 4.4.0 contain an inefficient algorithmic complexity issue (CWE-407) in the opt-in IndentationAwareTokenBuilder and IndentationAwareLexer. When producing DEDENT tokens, the token builder recomputes line numbers by re-scanning the entire preceding document text. A document whose indentation changes on most lines then takes quadratic time to tokenize. Because tokenization is synchronous, a crafted document of a few hundred kilobytes can block the Node.js event loop for tens of seconds. That causes a DoS for every user served by the same process. Languages built with the DefaultLexer and DefaultTokenBuilder are unaffected.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-09 16:47 UTC
CWE
Assigner
eclipse
CNA
References
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Eclipse Foundation | Eclipse Langium |
Affected:
3.2.0 , ≤ 4.4.0
(semver)
|
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CVE-2026-118492 (GCVE-0-2026-118492)
Vulnerability from cvelistv5 – Published: 2026-11-09 15:57 – Updated: 2026-11-09 15:57
VLAI
EPSS
VEX
Summary
In Eclipse Langium versions 3.0.0 and later, the langium-sprotty package does not HTML-escape diagnostic messages before rendering them in the default hover popup provided by `addHoverPopupHandler`. If a Langium grammar allows cross-reference text to contain HTML markup (such as through a STRING terminal), an unresolved cross-reference produces a diagnostic message that includes the literal ref text. When a Sprotty diagram is opened for a malicious source file under these conditions, and a user hovers over the corresponding error marker, attacker-controlled JavaScript can execute in the browser or webview.
CWE
Assigner
eclipse
CNA
References
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Eclipse Foundation | Eclipse Langium |
Affected:
3.0.0 , ≤ 4.4.0
(semver)
|
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