Versions of the package markdown-it from 13.0.0 and before 14.1.1 are vulnerable to Regular Expression Denial of Service (ReDoS) due to the use of the regex /*+$/ in the linkify function. An attacker can supply a long sequence of * characters followed by a non-matching character, which triggers excessive backtracking and may lead to a denial-of-service condition.
Weakness
The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles.
Extended Description
Attackers can create crafted inputs that
intentionally cause the regular expression to use
excessive backtracking in a way that causes the CPU
consumption to spike.
Potential Mitigations
Related Attack Patterns
References
- https://gist.github.com/ltduc147/c9abecae1b291ede4f692f2ab988c917
- https://github.com/markdown-it/markdown-it/blob/14.1.0/lib/rules_inline/linkify.mjs%23L33
- https://github.com/markdown-it/markdown-it/commit/4b4bbcae5e0990a5b172378e507b33a59012ed26
- https://security.snyk.io/vuln/SNYK-JS-MARKDOWNIT-10666750
- https://gist.github.com/ltduc147/c9abecae1b291ede4f692f2ab988c917
- https://security.snyk.io/vuln/SNYK-JS-MARKDOWNIT-10666750