Buffer overflow in Linux

CVE-2025-39810

In the Linux kernel, the following vulnerability has been resolved: bnxt_en: Fix memory corruption when FW resources change during ifdown bnxt_set_dflt_rings() assumes that it is always called before any TC has been created. So it doesn't take bp->num_tc into account and assumes that it is always 0 or 1. In the FW resource or capability change scenario, the FW will return flags in bnxt_hwrm_if_change() that will cause the driver to reinitialize and call bnxt_cancel_reservations(). This will lead to bnxt_init_dflt_ring_mode() calling bnxt_set_dflt_rings() and bp->num_tc may be greater than 1. This will cause bp->tx_ring[] to be sized too small and cause memory corruption in bnxt_alloc_cp_rings(). Fix it by properly scaling the TX rings by bp->num_tc in the code paths mentioned above. Add 2 helper functions to determine bp->tx_nr_rings and bp->tx_nr_rings_per_tc.

Vulnerability class: Buffer Overflow

EPSS: 0.002 (6.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/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-2025-39810?
CVE-2025-39810 is a high-severity vulnerability in Linux, classified under Out-of-bounds Write. CVSS score: 7.8/10. Published 2025-09-16.
How severe is CVE-2025-39810?
High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2025-39810 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.