CVE-2026-93749

source-map-js through 1.2.1 Event Loop Denial of Service

Published Sep 18, 2026 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed
Description
source-map-js through 1.2.1 fails to validate the per-section offset line value in indexed source maps, allowing attackers to specify arbitrary numeric values. Attackers can supply extremely large offset line values that cause synchronous event loop blocking for extended periods, preventing the service from handling other requests.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-68fv-2mgg-jv7q source-map-js allows event-loop denial of service through indexed source-map section offsets
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared 7rulnik
7rulnik source-map-js
Vendors & Products 7rulnik
7rulnik source-map-js
Type Values Removed Values Added
Description source-map-js through 1.2.1 fails to validate the per-section offset line value in indexed source maps, allowing attackers to specify arbitrary numeric values. Attackers can supply extremely large offset line values that cause synchronous event loop blocking for extended periods, preventing the service from handling other requests.
Title source-map-js through 1.2.1 Event Loop Denial of Service
Weaknesses CWE-1284
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 8.7, 'vector': '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Sep 24, 2026, 2:23 PM
Reserved
Sep 18, 2026, 4:30 PM
Status
Awaiting Analysis
Published
Sep 18, 2026, 6:18 PM
Modified
Sep 22, 2026, 8:25 PM
Severity
Important
Public date
Sep 18, 2026, 5:51 PM