CVE Database · CVE-2021-22555
CVSS v3.1
8.3
EPSS
78.68%
Published
Jul 7, 2021
Modified
Oct 27, 2025
CISA Known Exploited Vulnerability
Added: 2025-10-06 · Due: 2025-10-27
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Public PoC / Exploit (10)
All weaponized →Links to public security research (Exploit-DB, Nuclei, Trickest, GitHub) for defensive use only.
Description
A heap out-of-bounds write affecting Linux since v2.6.19-rc1 was discovered in net/netfilter/x_tables.c. This allows an attacker to gain privileges or cause a DoS (via heap memory corruption) through user name space
CVSS Vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:HWeaknesses (CWE)
Affected Products (42)
References (19)