VULNERABILITY INTELLIGENCE

CVE-2021-20322

CVSS score7.4 HIGH
EPSS probability6.90%
CISA KEVNot currently listed
Published2022-02-18
Last modified2026-07-30
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Description

A flaw in the processing of received ICMP errors (ICMP fragment needed and ICMP redirect) in the Linux kernel functionality was found to allow the ability to quickly scan open UDP ports. This flaw allows an off-path remote user to effectively bypass the source port UDP randomization. The highest threat from this vulnerability is to confidentiality and possibly integrity, because software that relies on UDP source port randomization are indirectly affected as well.

Weakness classification

  • secalert@redhat.com: CWE-330
  • nvd@nist.gov: CWE-330

Primary references