Raw vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:HSummary
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 Exploitation for Client Execution (T1203); ranked in the top 7% 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
- 🇪🇺 ENISA EUVD: EUVD-2021-9736
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)
- KEV Date Added
- 11 April 2022
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
—
—
- 1 hardening rule · 1 OS baseline
—
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.
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.
Security testing in development can detect double-free conditions before release.
Secure development life cycle includes memory-safety practices that can prevent double-free bugs.
Application security requirements can mandate memory-safety rules that reduce double-free risk.
Secure system architecture and engineering principles can prescribe safe memory-management patterns.
Secure coding standards directly address proper use of free() and similar functions.
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` (authoritative 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. prevents CWE-415