Linux KernelOperating system · Linux
CVE-2021-47453
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: ice: Avoid crash from unnecessary IDA free In the remove path, there is an attempt to free the aux_idx IDA whether it was allocated or not. This can potentially cause a crash when unloading the driver on systems that do not initialize support for RDMA. But, this free cannot be gated by the status bit for RDMA, since it is allocated if the driver detects support for RDMA at probe time, but the driver can enter into a state where RDMA is not supported after the IDA has been allocated at probe time and this would lead to a memory leak. Initialize aux_idx to an invalid value and check for a valid value when unloading to determine if an IDA free is necessary.
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 analysisAllocated memory is never released on some path, so a long-running service or a repeatedly triggered request steadily consumes memory until performance degrades or the process crashes. Attackers exploit it by simply driving the leaking path. Remediation is pairing every allocation with a release and using ownership patterns or tooling to catch what leaks.
General guidance for the memory leak 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
>= 5.14, < 5.14.15= 5.15CVSS 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 · scoped5.14.15
Linux Kernel 5.14.15+ or 5.16+ (or distribution vendor kernel update that includes commit 73e30a62b19b)
- Upgrade the Linux kernel to version 5.14.15 or later, or to version 5.16 or later
- Alternatively, apply the vendor kernel patch for your distribution that addresses this CVE
- After upgrading, reboot the system to load the fixed kernel
- Verify the fix is applied by checking the kernel version: `uname -r`
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-2021-47453 — 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-2021-47453 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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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data