CVE-2021-4001
4.1 · MEDIUMOverview
CVE-2021-4001 is a medium-severity vulnerability affecting linux linux_kernel. It was published on January 21, 2022 and has a CVSS 3.1 base score of 4.1 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 4.1, rated MEDIUM. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
Technical Description
A race condition was found in the Linux kernel's ebpf verifier between bpf_map_update_elem and bpf_map_freeze due to a missing lock in kernel/bpf/syscall.c. In this flaw, a local user with a special privilege (cap_sys_admin or cap_bpf) can modify the frozen mapped address space. This flaw affects kernel versions prior to 5.16 rc2.
Remediation
Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| linux | linux_kernel | 0 | Affected |
References
Frequently Asked Questions
What is CVE-2021-4001?
CVE-2021-4001 is a medium-severity vulnerability affecting linux linux_kernel. It was published on January 21, 2022 and has a CVSS 3.1 base score of 4.1 (MEDIUM).
How severe is CVE-2021-4001?
This vulnerability has a CVSS 3.1 base score of 4.1, rated MEDIUM. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2021-4001?
Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-4001?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-4001 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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