Vulnerability in FreeBSD
CVE-2026-49415
During execve(2) of a SUID binary, the new virtual address space is installed before the process credentials are updated. During this window, a process running as the same user can access the target process's memory via procfs or linprocfs, because the kernel's debugging permission check still saw the original credentials. An unprivileged local user can exploit this race to modify the address space of a SUID binary before its credentials are elevated, potentially gaining full control of the affected system.
Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.004 (27.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 27.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.004 · change: +0.001
Affected products
- FreeBSD — versions 14.3, 15.0, 14.4
Weakness classification (CWE)
References
- security.freebsd.org/advisories/FreeBSD-SA-26:39.execve.asc (vendor-advisory, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-49415?
- CVE-2026-49415 is a high-severity vulnerability in FreeBSD, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 8.8/10. Published 2026-08-19.
- How severe is CVE-2026-49415?
- High severity. CVSS v3 base score is 8.8 out of 10.