All the vulnerabilities related to the version 2.6.1 of the package
Macro in MathJax running untrusted Javascript within a web browser
MathJax version prior to version 2.7.4 contains a Cross Site Scripting (XSS) vulnerability in the \unicode{} macro that can result in Potentially untrusted Javascript running within a web browser. This attack appear to be exploitable via The victim must view a page where untrusted content is processed using Mathjax. This vulnerability appears to have been fixed in 2.7.4 and later.
MathJax Regular expression Denial of Service (ReDoS)
Mathjax up to v2.7.9 was discovered to contain two Regular expression Denial of Service (ReDoS) vulnerabilities in MathJax.js via the components pattern and markdownPattern. NOTE: the vendor disputes this because the regular expressions are not applied to user input; thus, there is no risk.