const regex = /(?i)(%(25){0,}20|\s)*(%(25){0,}24|\$)(%(25){0,}20|\s)*(%(25){0,}7B|{)(%(25){0,}20|\s)*(%(25){0,}(6A|4A)|J)(%(25){0,}(6E|4E)|N)(%(25){0,}(64|44)|D)(%(25){0,}(69|49)|I)(%(25){0,}20|\s)*(%(25){0,}3A|:)[\w\%]+(%(25){1,}3A|:)(%(25){1,}2F|\/)[^\n]+/gm;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('(?i)(%(25){0,}20|\\s)*(%(25){0,}24|\\$)(%(25){0,}20|\\s)*(%(25){0,}7B|{)(%(25){0,}20|\\s)*(%(25){0,}(6A|4A)|J)(%(25){0,}(6E|4E)|N)(%(25){0,}(64|44)|D)(%(25){0,}(69|49)|I)(%(25){0,}20|\\s)*(%(25){0,}3A|:)[\\w\\%]+(%(25){1,}3A|:)(%(25){1,}2F|\\\/)[^\\n]+', 'gm')
const str = `Sample Log4j strings:
\${JNDI:LDAP://
\${JNDI:LDAPS://
\${JNDI:RMI://
\${JNDI:DNS://
\${JNDI:NIS://
\${JNDI:IIOP://
\${JNDI:CORBA://
\${JNDI:NDS://
\${JNDI:HTTPS://
\${JNDI:HTTP://
\$ { JNDI :LDAPS://
\$ { JNDI :LDAPS://
\${jNDi:l%252564ap://
JNDI = %6A%6E%64%69
jndi = %4A%4E%44%49
Multi-encoding log4j strings (without spaces):
%24%7B%6A%6E%64%69%3A%2F
%2524%257B%256A%256E%2564%2569%253A
%2524%257B%256A%256E%2564%2569%253A%252F
%252524%25257B%25256A%25256E%252564%252569%25253A%25252F
Multi-URL Encoded string characters:
(?i)
(%(25){0,}20|\\s)*
(%(25){0,}24|\$)
(%(25){0,}20|\\s)*
(%(25){0,}7B|{)
(%(25){0,}20|\\s)*
(%(25){0,}(6A|4A)|J)
(%(25){0,}(6E|4E)|N)
(%(25){0,}(64|44)|D)
(%(25){0,}(69|49)|I)
(%(25){0,}20|\\s)*
(%(25){0,}3A|:)
(%(25){0,}2F|\\/)
[\\w\\%]+
(%(25){0,}3A|:)
(%(25){0,}2F|\\/)
`;
// Reset `lastIndex` if this regex is defined globally
// regex.lastIndex = 0;
let m;
while ((m = regex.exec(str)) !== null) {
// This is necessary to avoid infinite loops with zero-width matches
if (m.index === regex.lastIndex) {
regex.lastIndex++;
}
// The result can be accessed through the `m`-variable.
m.forEach((match, groupIndex) => {
console.log(`Found match, group ${groupIndex}: ${match}`);
});
}
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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions