medium CVSS 5.5 EPSS <0.1%

CVE-2023-52732·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: ceph: blocklist the kclient when receiving corrupted snap trace When received corrupted snap trace we don't know what exactly has happened in MDS side. And we shouldn't continue IOs and metadatas access to MDS, which may corrupt or get incorrect contents. This patch will just block all the further IO/MDS requests immediately and then evict the kclient itself. The reason why we still need to evict the kclient just after blocking all the further IOs is that the MDS could revoke the caps faster.

Severity
medium
Software
Kernel
Fixed in
6.1.13
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at <0.1% — higher than 1% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Affected versions

From: 2.6.35

Until: 6.1.13

Fixed in: 6.1.13

How to fix this CVE

Update your Linux kernel to version 6.1.13 or later to address this Ceph filesystem vulnerability that can cause data corruption when corrupted snap traces are received from the MDS server. This patch implements defensive blocklisting to prevent further I/O operations when trace corruption is detected, protecting your cluster from inconsistent state propagation. Apply the update through your distribution's package manager and reboot the system to activate the patched kernel.

sudo dnf check-update kernel && sudo dnf upgrade kernel && sudo reboot

Defensia detects this vulnerability

How to check if you are affected

  1. Check current kernel version: uname -r | awk -F'.' '{print $1"."$2"."$3}'
  2. Verify if Ceph client is active: ps aux | grep -i ceph | grep -v grep
  3. Search system logs for snap trace errors: sudo grep -i 'snap trace\|corrupted trace' /var/log/kern.log /var/log/messages 2>/dev/null
  4. Confirm patch application by checking kernel build date: uname -v or dmesg | grep 'Linux version' and compare against release date of 6.1.13

FAQ

What is CVE-2023-52732?

This vulnerability exists in the Linux kernel's Ceph filesystem client when handling corrupted snapshot trace metadata from the MDS server. Without proper validation, the client would continue processing I/O operations with potentially inconsistent data, risking silent data corruption across the cluster.

Is CVE-2023-52732 being actively exploited?

No, this vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog and no public exploits are available. Exploitation requires either a compromised MDS server or a network-level man-in-the-middle attack to inject corrupted metadata.

What versions of Kernel are affected by CVE-2023-52732?

Linux kernel versions from 2.6.35 through 6.1.12 are affected. The vulnerability is patched in kernel 6.1.13 and all subsequent releases.

How do I check if my server is vulnerable to CVE-2023-52732?

Run 'uname -r' to display your kernel version. If the output shows version 6.1.12 or earlier, your system requires a kernel update. For versions between 2.6.35 and 6.1.12, the vulnerability is present.

Does Defensia detect CVE-2023-52732?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If the Linux kernel is installed on a monitored server, CVE-2023-52732 will appear in your dashboard with remediation steps.

Related Kernel CVEs

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CVE-2026-52914CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: batman-adv: fix fragment reassembly length accounting batman-adv keeps a running payload length for queued fragments and uses it to validate a fragment chain before reassembly. That accounting currently allows the accumulated fragment length to be truncated during updates. As a result, malformed fragment chains can bypass the intended validation and drive reassembly with inconsistent length state, leading to a local denial of service. Fix the accounting by storing the accumulated length in a length-typed field and rejecting update overflows before the existing validation logic runs. The fix was verified against the original reproducer and against valid fragment reassembly paths.
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References

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