CVE-2021-22555

8.3 HIGH CISA KEV - Actively Exploited
Published: July 07, 2021 Modified: October 27, 2025
View on NVD

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

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
http://packetstormsecurity.com/files/163528/Linux-Kernel-Netfilter-Heap-Out-Of-Bounds-Write.html
Source: cve-coordination@google.com
Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/163878/Kernel-Live-Patch-Security-Notice-LSN-0080-1.html
Source: cve-coordination@google.com
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/164155/Kernel-Live-Patch-Security-Notice-LSN-0081-1.html
Source: cve-coordination@google.com
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/164437/Netfilter-x_tables-Heap-Out-Of-Bounds-Write-Privilege-Escalation.html
Source: cve-coordination@google.com
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/165477/Kernel-Live-Patch-Security-Notice-LSN-0083-1.html
Source: cve-coordination@google.com
Exploit Third Party Advisory VDB Entry
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=9fa492cdc160cd27ce1046cb36f47d3b2b1efa21
Source: cve-coordination@google.com
Mailing List Patch Vendor Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=b29c457a6511435960115c0f548c4360d5f4801d
Source: cve-coordination@google.com
Mailing List Patch Vendor Advisory
https://github.com/google/security-research/security/advisories/GHSA-xxx5-8mvq-3528
Source: cve-coordination@google.com
Exploit Third Party Advisory
https://security.netapp.com/advisory/ntap-20210805-0010/
Source: cve-coordination@google.com
Third Party Advisory
http://packetstormsecurity.com/files/163528/Linux-Kernel-Netfilter-Heap-Out-Of-Bounds-Write.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/163878/Kernel-Live-Patch-Security-Notice-LSN-0080-1.html
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/164155/Kernel-Live-Patch-Security-Notice-LSN-0081-1.html
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/164437/Netfilter-x_tables-Heap-Out-Of-Bounds-Write-Privilege-Escalation.html
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/165477/Kernel-Live-Patch-Security-Notice-LSN-0083-1.html
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory VDB Entry
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=9fa492cdc160cd27ce1046cb36f47d3b2b1efa21
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Patch Vendor Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=b29c457a6511435960115c0f548c4360d5f4801d
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Patch Vendor Advisory
https://github.com/google/security-research/security/advisories/GHSA-xxx5-8mvq-3528
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory
https://security.netapp.com/advisory/ntap-20210805-0010/
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-22555
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
US Government Resource

19 reference(s) from NVD

Quick Stats

CVSS v3 Score
8.3 / 10.0
EPSS (Exploit Probability)
85.3%
99th percentile
Exploitation Status
Actively Exploited
Remediation due: 2025-10-27

Weaknesses (CWE)

CWE-787 CWE-787

Affected Vendors

netapp brocade linux

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