CVE Vulnerabilities

CVE-2021-26813

Inefficient Regular Expression Complexity

Published: Mar 03, 2021 | Modified: Nov 07, 2023
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
5 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P
RedHat/V2
RedHat/V3
Ubuntu

markdown2 >=1.0.1.18, fixed in 2.4.0, is affected by a regular expression denial of service vulnerability. If an attacker provides a malicious string, it can make markdown2 processing difficult or delayed for an extended period of time.

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
Markdown2 Markdown2_project 1.0.1.18 *

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