Severity: moderate

Regular Expression Denial of Service



Affected versions of acorn are vulnerable to Regular Expression Denial of Service. A regex in the form of /[x-\ud800]/u causes the parser to enter an infinite loop. The string is not valid UTF16 which usually results in it being sanitized before reaching the parser. If an application processes untrusted input and passes it directly to acorn, attackers may leverage the vulnerability leading to Denial of Service.


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Advisory timeline

  1. published

    Advisory Published
    Mar 6th, 2020
  2. reported

    Reported by Peter van der Zee
    Mar 2nd, 2020