CVE-2026-4747 (GCVE-0-2026-4747)

Vulnerability from cvelistv5 – Published: 2026-03-26 06:21 – Updated: 2026-03-27 03:55
VLAI?
Title
Remote code execution via RPCSEC_GSS packet validation
Summary
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.
Severity ?
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-121 - Stack-based Buffer Overflow
Assigner
References
Impacted products
Vendor Product Version
FreeBSD FreeBSD Affected: 15.0-RELEASE , < p5 (release)
Affected: 14.4-RELEASE , < p1 (release)
Affected: 14.3-RELEASE , < p10 (release)
Affected: 13.5-RELEASE , < p11 (release)
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Date Public ?
2026-03-26 05:00
Credits
Nicholas Carlini using Claude, Anthropic
Show details on NVD website
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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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