CVE-2022-49362
Published: 26 February 2025
Summary
CVE-2022-49362 is a high-severity Use After Free (CWE-416) vulnerability in Linux Linux Kernel. Its CVSS base score is 7.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 33.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SI-2 (Flaw Remediation) and RA-5 (Vulnerability Monitoring and Scanning).
Deeper analysis
CVE-2022-49362 is a use-after-free vulnerability in the Linux kernel's NFSD component, specifically within the nfsd_file_put() function. The issue arises because nfsd_file_put_noref() can free the @nf object, but the code subsequently dereferences @nf immediately upon its return, leading to potential memory corruption. This flaw is classified under CWE-416 (Use After Free) and carries a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), indicating high impact on confidentiality, integrity, and availability.
A local attacker with low privileges can exploit this vulnerability due to its low attack complexity and lack of user interaction requirements. Successful exploitation could allow the attacker to trigger the use-after-free condition, potentially resulting in arbitrary code execution, data corruption, or kernel crashes within the context of the NFSD process.
Mitigation involves applying the relevant stable kernel patches, as detailed in the upstream commit references. These patches address the issue by ensuring that @nf is not dereferenced immediately after the call to nfsd_file_put_noref(), preventing the use-after-free scenario across affected kernel versions.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2022-54867
Vulnerability details
In the Linux kernel, the following vulnerability has been resolved: NFSD: Fix potential use-after-free in nfsd_file_put() nfsd_file_put_noref() can free @nf, so don't dereference @nf immediately upon return from nfsd_file_put_noref().
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Local use-after-free in kernel NFSD enables exploitation for privilege escalation to achieve arbitrary code execution or kernel impact.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly requires timely remediation of identified flaws like this use-after-free vulnerability through application of stable kernel patches.
Implements memory protection mechanisms such as ASLR, DEP, and kernel protections to mitigate exploitation of the use-after-free condition leading to code execution.
Provides vulnerability scanning to identify systems with vulnerable Linux kernel versions affected by this NFSD use-after-free flaw.