Remote code execution via RPCSEC_GSS packet validation_CVE-2026-4747

8.8 / 10

HIGH

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

Description

Each RPCSEC_GSS data packet is validated by a routine which checks a signature in the packet. This routine copies a portion of the packet into a stack buffer, but fails to ensure that the buffer is sufficiently large, and a malicious client can trigger a stack overflow. Notably, this does not require the client to authenticate itself first.

As kgssapi.ko's RPCSEC_GSS implementation is vulnerable, remote code execution in the kernel is possible by an authenticated user that is able to send packets to the kernel's NFS server while kgssapi.ko is loaded into the kernel.

In userspace, applications which have librpcgss_sec loaded and run an RPC server are vulnerable to remote code execution from any client able to send it packets. We are not aware of any such applications in the FreeBSD base system.

Basic Information

ID CVE-2026-4747

Source freebsd

Published Mar 26, 2026 at 06:21

Modified Apr 2, 2026 at 03:55

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
FreeBSD FreeBSD 13.5-RELEASE

CWE Classification

CWE-121

References

security.freebsd.org /advisories/FreeBSD-SA-26:08.rpcsec_gss.asc

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    "published": "2026-03-26T06:21:12.735Z",
    "modified": "2026-04-02T03:55:35.253Z",
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