Vulnerability in FreeBSD

CVE-2026-49428

Certain system calls, such open(2) with the O_TRUNC flag set, and fspacectl(2), could incorrectly free memory in largepage objects. These operations are not permitted on largepage objects, but the implementation did not verify this. An unprivileged local user can abuse the bug to access freed kernel memory. This can be exploited to escalate privileges.

Vulnerability class: Mass Assignment

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.4 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (25.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 25.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-49428: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.001

Affected products

  • FreeBSD — versions 14.3, 15.0, 14.4

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-49428?
CVE-2026-49428 is a high-severity vulnerability in FreeBSD, classified under Improperly Controlled Modification of Dynamically-Determined Object Attributes. CVSS score: 8.4/10. Published 2026-08-19.
How severe is CVE-2026-49428?
High severity. CVSS v3 base score is 8.4 out of 10.