high CVSS 8.8 EPSS 0.19%

CVE-2025-39862·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7915: fix list corruption after hardware restart Since stations are recreated from scratch, all lists that wcids are added to must be cleared before calling ieee80211_restart_hw. Set wcid->sta = 0 for each wcid entry in order to ensure that they are not added again before they are ready.

Severity
high
Software
Kernel
Fixed in
6.16.6
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 0.19% — higher than 8% 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-2025-39862 scores 8.8 on CVSS, so a successful attack would be serious — but at 0.19%, 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: 6.2

Until: 6.16.6

Fixed in: 6.16.6

How to fix this CVE

Update your Linux kernel to version 6.16.6 or later to patch a critical list corruption vulnerability in the MediaTek MT7915 WiFi driver that occurs during hardware restart operations. This vulnerability can cause kernel memory corruption and system instability when wireless devices are reinitialized. Apply the kernel update immediately and schedule a reboot to activate the patched version.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check your installed kernel version with 'uname -r' and compare against the vulnerable range (6.2 to 6.16.5)
  2. Step 2: Verify if MT7915 WiFi driver is loaded by running 'lsmod | grep mt7915' or check 'ethtool -i <interface>' for driver details
  3. Step 3: Search kernel logs for hardware restart events and list corruption indicators with 'dmesg | grep -E "mt7915|wcid|list_corruption|restart"'
  4. Step 4: After patching, confirm the new kernel version with 'uname -r' and verify it shows 6.16.6 or later

FAQ

What is CVE-2025-39862?

This vulnerability affects the MediaTek MT7915 WiFi driver in the Linux kernel, where station list structures become corrupted when the wireless hardware undergoes a restart cycle. The driver fails to properly clear internal station lists before reinitializing, causing stale memory references that can lead to kernel crashes or memory corruption.

Is CVE-2025-39862 being actively exploited?

No, there is no evidence of active exploitation in the wild, and no public exploits are available. However, the high CVSS score (8.8) reflects the severity of potential local impacts.

What versions of Kernel are affected by CVE-2025-39862?

Linux kernel versions 6.2 through 6.16.5 are vulnerable. Systems running kernel 6.16.6 or later, or versions before 6.2, are not affected.

How do I check if my server is vulnerable to CVE-2025-39862?

Run 'uname -r' to get your kernel version; if it falls between 6.2 and 6.16.5 and you have an MT7915 wireless device (check with 'lsmod | grep mt7915'), your system is vulnerable.

Does Defensia detect CVE-2025-39862?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Linux kernel is installed on a monitored server, CVE-2025-39862 will appear in your dashboard with remediation steps.

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References

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