Vulnerability in 7rulnik Source-Map-Js
CVE-2026-93749
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (39.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 39.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.005 · change: -0.002
Affected products
Weakness classification (CWE)
References
- github.com/7rulnik/source-map-js/issues/76 (issue-tracking)
- github.com/7rulnik/source-map-js (product)
- github.com/7rulnik/source-map-js/blob/c1cd8904bb7bd0c7fb5879fcda48134d82a27934/… (technical-description)
- www.vulncheck.com/advisories/source-map-js-through-1.2.1-event-loop-denial-of-s… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-93749?
- CVE-2026-93749 is a high-severity vulnerability in 7rulnik Source-Map-Js, classified under Improper Validation of Specified Quantity in Input. CVSS score: 7.5/10. Published 2026-09-18.
- How severe is CVE-2026-93749?
- High severity. CVSS v3 base score is 7.5 out of 10.