Vulnerability in Linux
CVE-2026-45952
In the Linux kernel, the following vulnerability has been resolved: eth: fbnic: Add validation for MTU changes Increasing the MTU beyond the HDS threshold causes the hardware to fragment packets across multiple buffers. If a single-buffer XDP program is attached, the driver will drop all multi-frag frames. While we can't prevent a remote sender from sending non-TCP packets larger than the MTU, this will prevent users from inadvertently breaking new TCP streams. Traditionally, drivers supported XDP with MTU less than 4Kb (packet per page). Fbnic currently prevents attaching XDP when MTU is too high. But it does not prevent increasing MTU after XDP is attached.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.002 (4.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 4th percentile — 4.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.000
Affected products
- Linux — versions 1b0a3950dbd4fa278dc33401a4faba2a23307a16, 6.18, 0
- Linux Kernel
References
Frequently asked questions
- What is CVE-2026-45952?
- CVE-2026-45952 is a medium-severity vulnerability in Linux. CVSS score: 5.5/10. Published 2026-05-27.
- How severe is CVE-2026-45952?
- Medium severity. CVSS v3 base score is 5.5 out of 10.