Linux KernelOperating system · Linux
CVE-2023-1838
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 · uneditedA use-after-free flaw was found in vhost_net_set_backend in drivers/vhost/net.c in virtio network subcomponent in the Linux kernel due to a double fget. This flaw could allow a local attacker to crash the system, and could even lead to a kernel information leak problem.
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 · high confidenceA use-after-free vulnerability in vhost_net_set_backend in drivers/vhost/net.c in the Linux kernel's virtio network subcomponent, caused by improper handling of a double fget operation. This allows a local attacker to potentially crash the system or leak kernel memory.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
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
>= 4.13, < 4.14.317>= 4.15, < 4.19.245>= 4.20, < 5.4.196>= 5.5, < 5.10.118>= 5.11, < 5.15.42>= 5.16, < 5.17.10all versionsall versionsall versionsall versionsall versionsCVSS 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
- High
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify if vhost_net module is loadedRun 'lsmod | grep vhost' or 'modinfo vhost_net' to check if the vhost_net kernel module is present and loadedAffected if vhost_net module is loaded and kernel version falls within the affected ranges
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Determine the running kernel versionRun 'uname -r' to get the kernel version, then compare against affected ranges: < 4.14.317, 4.15-4.19.245, 4.20-5.4.196, 5.5-5.10.118, 5.11-5.15.42, or 5.16-5.17.10Affected if Kernel version is within any of the listed vulnerable ranges
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Check if virtio network devices are in useRun 'ls /dev/vhost-net' or check for virtio network interfaces via 'ip link show' looking for virtio-related network devicesAffected if Virtio network devices exist and kernel version is vulnerable
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Identify NetApp H-series storage systemsOn NetApp systems, run 'system node show' or check hardware model via 'halctl show' or similar vendor commands to determine if the system is an H300s, H410c, H410s, H500s, or H700s modelAffected if System is a NetApp H300s, H410c, H410s, H500s, or H700s model (all versions affected)
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Verify vhost_net backend configurationCheck /sys/kernel/debug/vhost/net or use 'ls -la /dev/vhost*' to see if vhost-net device nodes exist, indicating active vhost-net backend usageAffected if vhost_net backend is configured and kernel version is vulnerable
A system is affected if it runs a Linux kernel version within the vulnerable ranges AND uses vhost_net with virtio networking, or if it is a NetApp H300s/H410c/H410s/H500s/H700s storage system.
Generated from the published advisory. Verify against your own configuration.
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 · scoped4.14.3174.19.2455.4.196
Apply the kernel security patch for CVE-2023-1838, which corrects the double fget logic, or update to a kernel version containing the fix. In production environments, test virtio networking functionality thoroughly after applying the update.
Linux kernel >= 4.14.317, >= 4.19.245, >= 5.4.196, or >= 5.10.118 (or later stable releases)
- 1. Identify the currently running Linux kernel version using `uname -r`
- 2. Determine which kernel branch your version belongs to (4.14, 4.19, 5.4, or 5.10 series)
- 3. For mainline Linux kernels: upgrade to kernel version 4.14.317 or later, 4.19.245 or later, 5.4.196 or later, or 5.10.118 or later
- 4. For enterprise distributions (RHEL, Ubuntu, Debian, etc.): apply vendor-provided kernel security updates that include the fix for CVE-2023-1838
- 5. For embedded devices (H300s, H410c, H410s, H500s, H700s): contact Huawei for vendor-specific firmware updates that address this vulnerability
- 6. After applying the update, reboot the system to load the fixed kernel
- 7. Verify the fix by checking `uname -r` shows a version >= the appropriate fixed release and confirm the vulnerability is resolved with a kernel panic test or log inspection
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Linux Kernel
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing8.0 h
- Review / QA3.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,368.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-1838 — 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-2023-1838 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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