Linux KernelOperating system · Linux
CVE-2021-47203
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 · uneditedIn the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Fix list_add() corruption in lpfc_drain_txq() When parsing the txq list in lpfc_drain_txq(), the driver attempts to pass the requests to the adapter. If such an attempt fails, a local "fail_msg" string is set and a log message output. The job is then added to a completions list for cancellation. Processing of any further jobs from the txq list continues, but since "fail_msg" remains set, jobs are added to the completions list regardless of whether a wqe was passed to the adapter. If successfully added to txcmplq, jobs are added to both lists resulting in list corruption. Fix by clearing the fail_msg string after adding a job to the completions list. This stops the subsequent jobs from being added to the completions list unless they had an appropriate failure.
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 analysisThe program writes past the bounds of a buffer, overwriting adjacent memory an attacker can turn to their advantage. Crafted input can overwrite control data and redirect execution. Remediation is validating every index and length before a write, plus modern memory-safety mitigations.
General guidance for the out-of-bounds write class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →
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
< 4.4.293>= 4.5, < 4.9.291>= 4.10, < 4.14.256>= 4.15, < 4.19.218>= 4.20, < 5.4.162>= 5.5, < 5.10.82>= 5.11, < 5.15.5CVSS 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
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:L/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 · scoped4.4.2934.9.2914.14.256
Linux kernel 4.4.293, 4.9.291, 4.14.256, or 4.19.218 (or later stable release)
- Identify the currently running Linux kernel version using 'uname -r'
- Upgrade the Linux kernel to a version that includes the fix: 4.4.293 or later, 4.9.291 or later, 4.14.256 or later, or 4.19.218 or later
- Update the kernel package using the distribution's package manager (e.g., apt-get update && apt-get upgrade, yum update, or dnf update)
- Reboot the system to load the new kernel
- Verify the kernel has been upgraded by running 'uname -r' and confirming it shows a fixed version
Generated from the published advisory — verify against the referenced sources before acting.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-47203 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-47203 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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