CVE-2026-55520

A flaw was found in Protego, a pure-Python robots.txt parser. A remote attacker could exploit this vulnerability by providing a crafted robots.txt file containing numerous asterisks in Allow or Disallow directives. This causes exponential backtracking during URL wildcard matching, leading to a...

CVE-2026-55520

Protego is a pure-Python robots.txt parser with support for modern conventions. Prior to 0.6.2, protego.urlpattern.URLPattern.preparepatternforregex translates every asterisk in an Allow or Disallow directive into a lazy regular-expression wildcard, so a directive containing many asterisks create...

CVE-2026-55520 Protego: Exponential backtracking ReDoS in robots.txt URL wildcard matching

Protego is a pure-Python robots.txt parser with support for modern conventions. Prior to 0.6.2, protego.urlpattern.URLPattern.preparepatternforregex translates every asterisk in an Allow or Disallow directive into a lazy regular-expression wildcard, so a directive containing many asterisks create...

CVE-2026-55520

Protego is a pure-Python robots.txt parser. Prior to 0.6.2 , the _URLPattern._prepare_pattern_for_regex method in src/protego/_urlpattern.py translates every asterisk in an Allow or Disallow directive into a lazy regex wildcard. A directive containing many asterisks triggers exponential backtrack...