Denial of Service Vulnerability in Source-map-js by 7rulnik
CVE-2026-93749

8.7HIGH

Key Information:

Vendor

7rulnik

Status
Source-map-js
Vendor
CVE Published:
18 September 2026

What is CVE-2026-93749?

The source-map-js library, up to version 1.2.1, is susceptible to a Denial of Service vulnerability due to an insufficient validation of per-section offset line values in indexed source maps. Attackers can exploit this flaw by providing exceptionally large numeric values, causing synchronous event loop blocking. This disruption prevents the service from processing other requests, significantly impacting application performance and availability.

Affected Version(s)

source-map-js 0 <= 1.2.1

References

https://github.com/7rulnik/source-map-js/issues/76
issue-tracking
https://github.com/7rulnik/source-map-js
product
https://github.com/7rulnik/source-map-js/blob/c1cd8904bb7...
technical-description

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Wayde Shi (PayPal Cyber Security Team)
.