A denial of service (DoS) vulnerability has been identified in the JavaScript library microlight version 0.0.7. This library, used for syntax highlighting, does not limit the size of textual content it processes in HTML elements with the microlight class. When excessively large content (e.g., 100 million characters) is processed, the reset function in microlight.js consumes excessive memory and CPU resources, causing browser crashes or unresponsiveness. An attacker can exploit this vulnerability by tricking a user into visiting a malicious web page containing a microlight element with large content, resulting in a denial of service. NOTE: this is disputed by multiple parties because a large amount of memory and CPU resources is expected to be needed for content of that size.
https://github.com/github/advisory-database/pull/5730
https://gist.github.com/Rootingg/483b09b760d031b62b172f2153f3ed2a
Published: 2025-06-17
Updated: 2025-06-18
Named Vulnerability: unknown
Base Score: 1.2
Vector: CVSS2#AV:L/AC:H/Au:N/C:N/I:N/A:P
Severity: Low
Base Score: 2.9
Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Severity: Low
Base Score: 2
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Severity: Low
EPSS: 0.00018