Linux KernelOperating system · Linux

CVE-2022-3621

MEDIUM · 6.5 CVSS v3.1 Published 2022-10-20
Patch available
A vendor patch is available. No clean upgrade release — apply the published patch.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A vulnerability was found in Linux Kernel. It has been classified as problematic. Affected is the function nilfs_bmap_lookup_at_level of the file fs/nilfs2/inode.c of the component nilfs2. The manipulation leads to null pointer dereference. It is possible to launch the attack remotely. It is recommended to apply a patch to fix this issue. The identifier of this vulnerability is VDB-211920.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis

A detailed technical summary for this CVE is being prepared.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Linux KernelOperating system
Affected:all versions
Debian LinuxOperating system
Affected:= 10.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Patch available Apply the vendor patch
Vendor patch git.kernel.org →
Recommended fix Moderate confidence

Linux Kernel >= 5.19 (mainline) or vendor-supplied kernel with CVE-2022-3621 backport; Debian 10 requires kernel from buster-updates or backports

  1. Check current kernel version with: uname -r
  2. Check if nilfs2 module is loaded: lsmod | grep nilfs2 or modinfo nilfs2
  3. For Debian 10 (Buster): Update system with: apt update && apt upgrade to receive security backports
  4. If automatic upgrade is not available, manually install a newer kernel package from Debian backports or recompile with the upstream patch from commit 21a87d88c2253350e115029f14fe2a10a7e6c856
  5. Reboot into the updated kernel
  6. Verify nilfs2 functionality: mount -t nilfs2 <device> <mountpoint>
Caveat Kernel upgrade may require system reboot and could introduce regressions; nilfs2 mount options may need adjustment if the fix changed bmap behavior

Generated from the published advisory — verify against the referenced sources before acting.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2022-3621 in production — separate from our analysis above.

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What this is

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  • Version or environment caveats, and links to real fixes
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