CVE-2026-124683

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-124683", "assignerOrgId": "e51fbebd-6053-4e49-959f-1b94eeb69a2c", "state": "PUBLISHED", "assignerShortName": "eclipse", "dateReserved": "2026-11-09T10:36:46.112Z", "datePublished": "2026-11-09T16:02:50.370Z", "dateUpdated": "2026-11-09T16:47:45.873Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "e51fbebd-6053-4e49-959f-1b94eeb69a2c", "shortName": "eclipse", "dateUpdated": "2026-11-09T16:02:50.370Z"}, "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-407", "description": "CWE-407", "type": "CWE"}]}], "impacts": [{"capecId": "CAPEC-130", "descriptions": [{"lang": "en", "value": "CAPEC-130"}]}], "affected": [{"vendor": "Eclipse Foundation", "product": "Eclipse Langium", "versions": [{"status": "affected", "version": "3.2.0", "lessThanOrEqual": "4.4.0", "versionType": "semver"}], "defaultStatus": "unaffected"}], "descriptions": [{"lang": "en", "value": "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.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<p>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.</p>"}]}], "references": [{"url": "https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/1069"}, {"url": "https://github.com/eclipse-langium/langium/security/advisories/GHSA-297v-g8mm-qj4h"}, {"url": "https://gitlab.eclipse.org/security/cve-assignment/-/work_items/553"}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "subConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "subIntegrityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "HIGH", "baseScore": 8.7, "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}}], "credits": [{"lang": "en", "value": "https://github.com/blackrose-0xday", "type": "finder"}], "source": {"discovery": "UNKNOWN"}, "x_generator": {"engine": "Vulnogram 1.0.5"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-11-09T16:47:35.260234Z", "id": "CVE-2026-124683", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-11-09T16:47:45.873Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-124683", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-11-09T16:47:35.260234Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-11-09T16:47:40.715Z"}}], "cna": {"source": {"discovery": "UNKNOWN"}, "credits": [{"lang": "en", "type": "finder", "value": "https://github.com/blackrose-0xday"}], "impacts": [{"capecId": "CAPEC-130", "descriptions": [{"lang": "en", "value": "CAPEC-130"}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 8.7, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "HIGH", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "affected": [{"vendor": "Eclipse Foundation", "product": "Eclipse Langium", "versions": [{"status": "affected", "version": "3.2.0", "versionType": "semver", "lessThanOrEqual": "4.4.0"}], "defaultStatus": "unaffected"}], "references": [{"url": "https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/1069"}, {"url": "https://github.com/eclipse-langium/langium/security/advisories/GHSA-297v-g8mm-qj4h"}, {"url": "https://gitlab.eclipse.org/security/cve-assignment/-/work_items/553"}], "x_generator": {"engine": "Vulnogram 1.0.5"}, "descriptions": [{"lang": "en", "value": "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.", "supportingMedia": [{"type": "text/html", "value": "<p>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.</p>", "base64": false}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-407", "description": "CWE-407"}]}], "providerMetadata": {"orgId": "e51fbebd-6053-4e49-959f-1b94eeb69a2c", "shortName": "eclipse", "dateUpdated": "2026-11-09T16:02:50.370Z"}}}, "cveMetadata": {"cveId": "CVE-2026-124683", "state": "PUBLISHED", "dateUpdated": "2026-11-09T16:47:45.873Z", "dateReserved": "2026-11-09T10:36:46.112Z", "assignerOrgId": "e51fbebd-6053-4e49-959f-1b94eeb69a2c", "datePublished": "2026-11-09T16:02:50.370Z", "assignerShortName": "eclipse"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Eclipse Langium", "vendor": "Eclipse Foundation", "versions": [{"lessThanOrEqual": "4.4.0", "status": "affected", "version": "3.2.0", "versionType": "semver"}]}], "source": "emo@eclipse.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "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."}], "id": "CVE-2026-124683", "lastModified": "2026-11-12T18:44:06.563", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 8.7, "baseSeverity": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/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", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "emo@eclipse.org", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-124683", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-11-09T16:47:35.260234Z", "version": "2.0.3"}}]}, "published": "2026-11-09T17:17:27.690", "references": [{"source": "emo@eclipse.org", "url": "https://github.com/eclipse-langium/langium/security/advisories/GHSA-297v-g8mm-qj4h"}, {"source": "emo@eclipse.org", "url": "https://gitlab.eclipse.org/security/cve-assignment/-/work_items/553"}, {"source": "emo@eclipse.org", "url": "https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/1069"}], "sourceIdentifier": "emo@eclipse.org", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-407"}], "source": "emo@eclipse.org", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[3.2.0,4.4.0]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "manual", "scores": [{"score": 100.0, "source": "manual"}]}, "original": {"product": "Eclipse Langium", "source": "cna", "vendor": "Eclipse Foundation"}, "product": "eclipse_langium", "vendor": "eclipse"}], "created": "2026-11-09T17:30:08.681136+00:00", "title": "Inefficient Algorithmic Complexity Causes Denial of Service in Eclipse Langium", "updated": "2026-11-12T20:09:28.565199+00:00", "vendors": ["eclipse", "eclipse$PRODUCT$eclipse_langium"]}