Security Resilience

CVE-2021-22600

Memory Safety in Linux Kernel 4.14.175 – 4.14.259

CISA KEVActive ExploitationEUVD ExploitedMemory Safety
Published
26 January 2022
Modified
24 October 2025
KEV Added
11 April 2022
Patch / advisory
View advisory
CVSS Score v3.1 6.6
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:H
EPSS Score 0.066 94th percentile
Risk Priority 75 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2021-22600 is a medium-severity Double Free (CWE-415) vulnerability in Linux Linux Kernel. Its CVSS base score is 6.6 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Steganography (T1001.002); ranked in the top 6% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

A double free vulnerability exists in the Linux kernel's packet socket implementation, specifically within the packet_set_ring() function in net/packet/af_packet.c. This flaw, tracked as CVE-2021-22600 and assigned CWE-415, allows improper memory handling during ring buffer operations and carries a CVSS score of 6.6.

A local user with low privileges can trigger the issue through crafted system calls. Successful exploitation may result in privilege escalation or a denial-of-service condition, though the attack requires specific conditions including user interaction and a hardened execution context.

Kernel developers addressed the bug in commit ec6af094ea28f0f2dda1a6a33b14cd57e36a9755. Security advisories from Debian and NetApp recommend upgrading to unaffected kernel versions or applying the referenced patch to mitigate the risk.

EU & UK References

Vulnerability Data

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

CWE(s)
CWE-415
KEV Date Added
11 April 2022

Related Threats

MITRE ATT&CK Enterprise Techniques

T1001.002 Steganography Command And Control
Adversaries may use steganographic techniques to hide command and control traffic to make detection efforts more difficult.
attack.mitre.org →
T1001.003 Protocol or Service Impersonation Command And Control
Adversaries may impersonate legitimate protocols or web service traffic to disguise command and control activity and thwart analysis efforts.
attack.mitre.org →
T1003.001 LSASS Memory Credential Access
Adversaries may attempt to access credential material stored in the process memory of the Local Security Authority Subsystem Service (LSASS).
attack.mitre.org →
T1003.002 Security Account Manager Credential Access
Adversaries may attempt to extract credential material from the Security Account Manager (SAM) database either through in-memory techniques or through the Windows Registry where the SAM database is stored.
attack.mitre.org →
T1003.004 LSA Secrets Credential Access
Adversaries with SYSTEM access to a host may attempt to access Local Security Authority (LSA) secrets, which can contain a variety of different credential materials, such as credentials for service accounts.
attack.mitre.org →
T1003.008 /etc/passwd and /etc/shadow Credential Access
Adversaries may attempt to dump the contents of <code>/etc/passwd</code> and <code>/etc/shadow</code> to enable offline password cracking.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-26545Same product: Debian Debian Linux
CVE-2023-1077Same product: Debian Debian Linux
CVE-2023-28464Same product: Linux Linux Kernel
CVE-2022-0185Same product: Linux Linux Kernelboth on KEV
CVE-2023-3111Same product: Debian Debian Linux
CVE-2023-0386Same product: Debian Debian Linuxboth on KEV
CVE-2024-1086Same product: Debian Debian Linuxboth on KEV
CVE-2023-2124Same product: Debian Debian Linux
CVE-2022-0995Same product: Linux Linux Kernelboth on KEV
CVE-2023-27537Same product: Netapp H300S

Affected Assets

netapp
8300 firmware
all versions
netapp
8700 firmware
all versions
netapp
a400 firmware
all versions
netapp
c400 firmware
all versions
linux
linux kernel
4.14.175 — 4.14.259 · 4.19.114 — 4.19.222 · 5.4.29 — 5.4.168
debian
debian linux
10.0, 9.0
netapp
h410c firmware
all versions
netapp
h300s firmware
all versions
netapp
h500s firmware
all versions
netapp
h700s firmware
all versions
+1 more product configuration(s) — see NVD for full list

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 1 hardening rule · 1 OS baseline
Validate
Prove the fix (OWASP ASVS)

—

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 partial match
blocks

Secure SDLC practices directly prevent double-free errors via static analysis, safe memory APIs, and testing.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.5.32 Intellectual property rights partial match
removes

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248590 OL 8 must clear the page allocator to prevent use-after-free attacks. blocks CWE-415

References