CVE-2026-93749

high

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.

References

https://www.vulncheck.com/advisories/source-map-js-through-1.2.1-event-loop-denial-of-service

https://github.com/7rulnik/source-map-js/issues/76

https://github.com/7rulnik/source-map-js/blob/c1cd8904bb7bd0c7fb5879fcda48134d82a27934/lib/source-node.js#L115-L118

https://github.com/7rulnik/source-map-js

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-83254

Details

Source: Mitre, NVD

Published: 2026-09-18

Updated: 2026-09-22

Named Vulnerability: GHSA-68fv-2mgg-jv7q

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

CVSS v4

Base 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

Severity: High

EPSS

EPSS: 0.0063