py-pygments -- multiple DoS vulnerabilities

Red Hat reports:

An infinite loop in SMLLexer in Pygments versions 1.5 to 2.7.3 may lead to denial of service when performing syntax highlighting of a Standard ML (SML) source file, as demonstrated by input that only contains the “exception” keyword.

Ben Caller reports:

In pygments 1.1+, fixed in 2.7.4, the lexers used to parse programming languages rely heavily on regular expressions.
Some of the regular expressions have exponential or cubic worst-case complexity and are vulnerable to ReDoS.
By crafting malicious input, an attacker can cause a denial of service.