vulnerability
Red Hat: CVE-2021-20322: CVE-2021-20322 kernel: new DNS Cache Poisoning Attack based on ICMP fragment needed packets replies (Multiple Advisories)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 6 | (AV:N/AC:M/Au:N/C:P/I:P/A:N) | Feb 18, 2022 | May 13, 2022 | Aug 11, 2025 |
Severity
6
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:N)
Published
Feb 18, 2022
Added
May 13, 2022
Modified
Aug 11, 2025
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.
Solutions
no-fix-redhat-rpm-packageredhat-upgrade-kernelredhat-upgrade-kernel-rt
NEW
Explore Exposure Command
Confidently identify and prioritize exposures from endpoint to cloud with full attack surface visibility and threat-aware risk context.