Secuno
ENNL
Book demo

CVE-2021-22600

Linux Kernel Privilege Escalation

6.6 MEDIUMActively exploited (CISA KEV)EPSS 6.59%
  1. Published26 Jan 2022
  2. Added to CISA KEV11 Apr 2022
  3. Remediation due2 May 2022
Actively exploited (CISA KEV)

Linux Kernel contains a flaw in the packet socket (AF_PACKET) implementation which could lead to incorrectly freeing memory. A local user could exploit this for denial-of-service (DoS) or possibly for privilege escalation.

Added to KEV: 11 Apr 2022Federal remediation due: 2 May 2022

Description

A double free bug in packet_set_ring() in net/packet/af_packet.c can be exploited by a local user through crafted syscalls to escalate privileges or deny service. We recommend upgrading kernel past the effected versions or rebuilding past ec6af094ea28f0f2dda1a6a33b14cd57e36a9755

CVSS 3.1 breakdown

Attack vectorLocal
Attack complexityHigh
Privileges requiredLow
User interactionRequired
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityHigh
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:H

Affected products

Debian Linux10.0 · 9.0
Linux Kernel≥ 4.14.175 < 4.14.259 · ≥ 4.19.114 < 4.19.222 · ≥ 5.11 < 5.15.11 · ≥ 5.4.29 < 5.4.168
Netapp 8300 Firmwareall versions
Netapp 8700 Firmwareall versions
Netapp A400 Firmwareall versions
Netapp C400 Firmwareall versions
Netapp H300s Firmwareall versions
Netapp H410c Firmwareall versions
Netapp H410s Firmwareall versions
Netapp H500s Firmwareall versions
Netapp H700s Firmwareall versions

Remediation

Fixed in
Linux Kernel≥ 4.14.259

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

CVE-2026-57599.8
A double free and use-after-free vulnerability in the RdbLoadDeletedNodes function of…
CVE-2026-890789.9
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 19.2 before…
CVE-2026-910188.8
lwIP (Lightweight IP) has a double free vulnerability, which could crash the system,…
CVE-2026-201358.6
A vulnerability in the TLS 1.3 implementation in Cisco Secure Firewall Threat Defense…
CVE-2026-845619.8
A double free issue was addressed with improved memory management. This issue is fixed…
CVE-2026-859218.2
Double free in Windows Secure Kernel Mode allows an authorized attacker to elevate…

Frequently asked

Is CVE-2021-22600 being actively exploited?

Yes. CVE-2021-22600 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 11 Apr 2022.

How severe is CVE-2021-22600?

CVE-2021-22600 has a CVSS 3.1 base score of 6.6, rated medium. EPSS estimates a 6.59% probability of exploitation.

Which products are affected by CVE-2021-22600?

Affected products include Debian Linux, Linux Kernel, Netapp 8300 Firmware, Netapp 8700 Firmware, Netapp A400 Firmware, and 6 more.

How do I fix CVE-2021-22600?

Upgrade affected software to a fixed version, for example Linux Kernel 4.14.259 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2021-22600 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, Secuno flags any affected asset as top-priority automatically. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation worksBook a demo

Get Patch this first every Monday

Five vulnerabilities that matter this week, ranked on real exploitation. Plain language, one email, no spam.

You can unsubscribe with one click from every issue. We handle your details as described in our privacy policy.

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.