high CVSS 7.8 EPSS <0.1%

CVE-2024-49966·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: ocfs2: cancel dqi_sync_work before freeing oinfo ocfs2_global_read_info() will initialize and schedule dqi_sync_work at the end, if error occurs after successfully reading global quota, it will trigger the following warning with CONFIG_DEBUG_OBJECTS_* enabled: ODEBUG: free active (active state 0) object: 00000000d8b0ce28 object type: timer_list hint: qsync_work_fn+0x0/0x16c This reports that there is an active delayed work when freeing oinfo in error handling, so cancel dqi_sync_work first. BTW, return status instead of -1 when .read_file_info fails.

Severity
high
Software
Kernel
Fixed in
6.11.3
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 2% 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.

Read the two together. CVE-2024-49966 scores 7.8 on CVSS, so a successful attack would be serious — but at <0.1%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.

Affected versions

From: 6.11

Until: 6.11.3

Fixed in: 6.11.3

How to fix this CVE

Update your Linux kernel to version 6.11.3 or later to resolve a memory management issue in the OCFS2 quota subsystem. The vulnerability occurs when quota initialization fails after scheduling a delayed work timer, leaving active kernel objects that trigger debug warnings and potential kernel instability. Applying this patch ensures proper cleanup of quota synchronization tasks during error conditions.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Run 'uname -r' to check your current kernel version and confirm if it falls within 6.11.0 to 6.11.2
  2. Check if OCFS2 is in use: grep -i ocfs2 /proc/filesystems or mount | grep ocfs2
  3. Review kernel logs for ODEBUG warnings: dmesg | grep -i 'ODEBUG.*dqi_sync_work' or journalctl -k | grep -i 'ODEBUG'
  4. Verify the fix by upgrading to kernel 6.11.3+ and confirming with 'uname -r', then reboot and monitor dmesg for absence of quota-related DEBUG_OBJECTS warnings

FAQ

What is CVE-2024-49966?

This vulnerability is a resource management flaw in the Linux kernel's OCFS2 quota handling where a delayed work timer is not properly cancelled during error recovery, causing active kernel objects to persist in memory and triggering debug assertions when freed.

Is CVE-2024-49966 being actively exploited?

No, there is no evidence of active exploitation or publicly available exploits for this vulnerability. It is a kernel stability issue rather than a direct privilege escalation vector.

What versions of Kernel are affected by CVE-2024-49966?

Linux kernel versions 6.11.0 through 6.11.2 are affected. The fix was released in kernel version 6.11.3.

How do I check if my server is vulnerable to CVE-2024-49966?

Run 'uname -r' and check if the output shows kernel 6.11.0, 6.11.1, or 6.11.2. Additionally, verify OCFS2 is active with 'grep ocfs2 /proc/filesystems' or 'mount | grep ocfs2'.

Does Defensia detect CVE-2024-49966?

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-2024-49966 will appear in your dashboard with remediation steps.

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References

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