high CVSS 7.1

CVE-2023-52507·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: nfc: nci: assert requested protocol is valid The protocol is used in a bit mask to determine if the protocol is supported. Assert the provided protocol is less than the maximum defined so it doesn't potentially perform a shift-out-of-bounds and provide a clearer error for undefined protocols vs unsupported ones.

Severity
high
Software
Kernel
Fixed in
6.5.8
Published
2024-03-02

Affected versions

From: 6.2

Until: 6.5.8

Fixed in: 6.5.8

How to fix this CVE

Update your Linux kernel to version 6.5.8 or later to resolve a protocol validation flaw in the NFC subsystem that could cause memory corruption. The vulnerability stems from insufficient bounds checking when processing NFC protocol identifiers, which may lead to out-of-bounds shift operations. Apply the kernel update through your distribution's package manager and reboot your system to ensure the fix is active.

sudo dnf update kernel kernel-devel && sudo reboot

Defensia detects this vulnerability

How to check if you are affected

  1. Check your current kernel version: uname -r (compare against 6.5.8 or later)
  2. Verify NFC drivers are loaded: lsmod | grep nfc (if empty, NFC is not enabled on this system)
  3. Review kernel build configuration: grep CONFIG_NFC /boot/config-$(uname -r) (look for CONFIG_NFC=y or CONFIG_NFC=m)
  4. After patching, confirm the update applied: reboot && uname -r (should show 6.5.8 or higher)

FAQ

What is CVE-2023-52507?

This vulnerability affects the Linux kernel's NFC (Near Field Communication) protocol handler, where improper validation of protocol parameters allows a local attacker to trigger an out-of-bounds shift operation, potentially corrupting kernel memory and causing denial of service or privilege escalation.

Is CVE-2023-52507 being actively exploited?

No, this vulnerability is not listed in CISA's Known Exploited Vulnerabilities (KEV) catalog and no public exploits are currently available.

What versions of Kernel are affected by CVE-2023-52507?

Linux kernel versions 6.2 through 6.5.7 are vulnerable; version 6.5.8 and later include the fix.

How do I check if my server is vulnerable to CVE-2023-52507?

Run `uname -r` and compare the output against 6.5.8; if your version is between 6.2 and 6.5.7, you are vulnerable. Additionally, check if NFC is enabled with `grep CONFIG_NFC /boot/config-$(uname -r)`.

Does Defensia detect CVE-2023-52507?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2023-52507 will appear in your dashboard with remediation steps.

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References

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