CVE Vulnerabilities

CVE-2021-4305

Inefficient Regular Expression Complexity

Published: Jan 05, 2023 | Modified: Apr 11, 2024
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
RedHat/V2
RedHat/V3
Ubuntu

A vulnerability was found in Woorank robots-txt-guard. It has been rated as problematic. Affected by this issue is the function makePathPattern of the file lib/patterns.js. The manipulation of the argument pattern leads to inefficient regular expression complexity. The exploit has been disclosed to the public and may be used. The name of the patch is c03827cd2f9933619c23894ce7c98401ea824020. It is recommended to apply a patch to fix this issue. The identifier of this vulnerability is VDB-217448.

Weakness

The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles.

Affected Software

Name Vendor Start Version End Version
Robots-txt-guard Bridgeline * 2021-02-07 (excluding)

Extended Description

      Attackers can create crafted inputs that
      intentionally cause the regular expression to use
      excessive backtracking in a way that causes the CPU
      consumption to spike.

Potential Mitigations

References