Linux KernelOperating system · Linux
CVE-2023-2598
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 flaw was found in the fixed buffer registration code for io_uring (io_sqe_buffer_register in io_uring/rsrc.c) in the Linux kernel that allows out-of-bounds access to physical memory beyond the end of the buffer. This flaw enables full local privilege escalation.
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 flaw in the Linux kernel's io_uring subsystem (io_sqe_buffer_register in io_uring/rsrc.c) allows out-of-bounds access to physical memory beyond the bounds of registered buffers. This memory corruption vulnerability in the fixed buffer registration code can be exploited by a local attacker to achieve full privilege escalation to root.
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
>= 6.3, < 6.3.2= h300s= h410c= h410s= h500s= h700sCVSS 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
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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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Check Linux kernel versionRun `uname -r` or `cat /proc/version` to get the running kernel versionAffected if Kernel version is 6.3.0 or 6.3.1 (versions >= 6.3 and < 6.3.2)
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Verify io_uring module is loadedRun `lsmod | grep io_uring` to check if the io_uring kernel module is loadedAffected if io_uring module is present and loaded into the kernel
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Check for io_uring usage in the systemRun `ls /proc/*/fd/* 2>/dev/null | grep -l io_uring` or check for open file descriptors referencing io_uring, or monitor for io_uring-related syscalls using `strace -c` on a test processAffected if Any process has an active io_uring file descriptor or is using io_uring system calls
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Check for fixed buffer registration usageSearch application code or runtime for calls to io_uring_register with IORING_REGISTER_BUFFERS flag, or trace io_uring_enter syscalls with register buffer operationsAffected if Applications are using fixed buffer registration (IORING_REGISTER_BUFFERS) with io_uring
A system is affected if it runs a Linux kernel between 6.3.0 and 6.3.1 (inclusive), has io_uring loaded, and uses io_uring's fixed buffer registration feature.
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 · scoped6.3.2
Apply the Linux kernel patch for CVE-2023-2598, which corrects bounds checking in io_sqe_buffer_register. Given the high CVSS score and privilege escalation capability, priority patching is warranted on systems using io_uring.
Linux Kernel 6.3.2 or later; contact HCI BMC vendor for firmware updates
- 1. Identify the current Linux kernel version running on the system using 'uname -r'
- 2. If the kernel version is >= 6.3.0 and < 6.3.2, plan for a system reboot after upgrading
- 3. Update the Linux kernel package to version 6.3.2 or later using the distribution's package manager (e.g., 'apt-get update && apt-get upgrade' for Debian/Ubuntu, 'yum update' for RHEL/CentOS)
- 4. After the kernel upgrade completes, reboot the system to load the fixed kernel
- 5. Verify the new kernel version is running with 'uname -r' and confirm it is 6.3.2 or higher
- 6. For the HCI Baseboard Management Controller models (h300s, h410c, h410s, h500s), contact the hardware vendor for firmware updates addressing this vulnerability, as no independent patch is available
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 / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,656.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-2598 — 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-2023-2598 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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