A ReDoS issue was discovered in pygments/lexers/smithy.py in pygments through 2.15.0 via SmithyLexer.

A ReDoS issue was discovered in pygments/lexers/smithy.py in Pygments until 2.15.0 via SmithyLexer.

A denial of service attack was discovered against pygments. Some of the regular expressions used to tokenise source code for highlighting have exponential complexity. A specially crafted input file could cause pygments to take effectively infinite time to parse, consuming CPU resources and denying access to the service.

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.