Use After Free in Linux

CVE-2025-39864

In the Linux kernel, the following vulnerability has been resolved: wifi: cfg80211: fix use-after-free in cmp_bss() Following bss_free() quirk introduced in commit 776b3580178f ("cfg80211: track hidden SSID networks properly"), adjust cfg80211_update_known_bss() to free the last beacon frame elements only if they're not shared via the corresponding 'hidden_beacon_bss' pointer.

Vulnerability class: Use-After-Free

EPSS: 0.002 (4.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-39864?
CVE-2025-39864 is a high-severity vulnerability in Linux, classified under Use After Free. CVSS score: 8.8/10. Published 2025-09-19.
How severe is CVE-2025-39864?
High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2025-39864 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.