Integer overflow in vt(4) CONS_HISTORY ioctl_CVE-2026-49416

7.8 / 10

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Description

The CONS_HISTORY ioctl handler did not adequately validate the requested history size. A large value caused an integer overflow in the buffer size calculation, resulting in a heap allocation smaller than expected. Subsequent initialization of the buffer wrote beyond the end of the allocation.

An unprivileged local user with access to a vt(4) device can trigger an out-of-bounds write in the kernel, potentially escalating privileges.

Basic Information

ID CVE-2026-49416

Source freebsd

Published Jun 27, 2026 at 09:25

Modified Jun 29, 2026 at 19:43

Affected Product

Vendor FreeBSD

Product FreeBSD

Version 15.0-RELEASE

Affected Versions FreeBSD FreeBSD 15.0-RELEASE
FreeBSD FreeBSD 14.4-RELEASE
FreeBSD FreeBSD 14.3-RELEASE

CWE Classification

CWE-190

References

security.freebsd.org /advisories/FreeBSD-SA-26:34.vt.asc

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    "published": "2026-06-27T09:25:12.443Z",
    "modified": "2026-06-29T19:43:34.595Z",
    "type": "cve",
    "title": "Integer overflow in vt(4) CONS_HISTORY ioctl",
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