medium CVSS 5.8

CVE-2024-27402·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: phonet/pep: fix racy skb_queue_empty() use The receive queues are protected by their respective spin-lock, not the socket lock. This could lead to skb_peek() unexpectedly returning NULL or a pointer to an already dequeued socket buffer.

Severity
medium
Software
Kernel
Fixed in
6.7.7
Published
2024-05-17

Affected versions

From: 6.7

Until: 6.7.7

Fixed in: 6.7.7

How to fix this CVE

Update your Linux kernel to version 6.7.7 or later to patch a race condition in the Phonet/PEP protocol handler that could cause memory access violations. This vulnerability affects the receive queue synchronization mechanism and may lead to kernel instability or information disclosure. Apply the kernel update through your distribution's package manager and reboot to activate the patched version.

sudo dnf upgrade kernel kernel-devel && sudo reboot

Defensia detects this vulnerability

How to check if you are affected

  1. Run 'uname -r' to check the currently running kernel version and confirm if it falls within the vulnerable range (6.7.0 to 6.7.7)
  2. Verify if Phonet/PEP protocol modules are loaded with 'lsmod | grep phonet' — if output is empty, the vulnerable code path is not active
  3. Check kernel logs for skb queue anomalies with 'sudo journalctl -k | grep -i "phonet\|pep\|queue\|null pointer"' to detect exploitation attempts
  4. Confirm the fix is applied by running 'uname -r' after reboot and verifying the kernel version is 6.7.7 or higher

FAQ

What is CVE-2024-27402?

CVE-2024-27402 is a race condition in the Linux kernel's Phonet/PEP protocol implementation where the socket lock fails to properly protect receive queue operations, allowing concurrent access to corrupted or dequeued socket buffers. This can result in kernel memory corruption or information leakage.

Is CVE-2024-27402 being actively exploited?

No, CVE-2024-27402 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits are available.

What versions of Kernel are affected by CVE-2024-27402?

Linux kernel versions 6.7.0 through 6.7.7 are affected. Kernel version 6.7.7 and later contain the fix.

How do I check if my server is vulnerable to CVE-2024-27402?

Run 'uname -r' to retrieve your kernel version. If the output shows version 6.7.0 through 6.7.7, your system is vulnerable. Additionally, check if Phonet protocol is loaded with 'lsmod | grep phonet'.

Does Defensia detect CVE-2024-27402?

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-2024-27402 will appear in your dashboard with remediation steps.

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References

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