CVE-2009-3726

Description

From CVE.org

The nfs4_proc_lock function in fs/nfs/nfs4proc.c in the NFSv4 client in the Linux kernel before 2.6.31-rc4 allows remote NFS servers to cause a denial of service (NULL pointer dereference and panic) by sending a certain response containing incorrect file attributes, which trigger attempted use of an open file that lacks NFSv4 state.

Statement

The Linux kernel as shipped with Red Hat Enterprise Linux 3 did not have support for NFSv4, and therefore is not affected by this issue. It was addressed in Red Hat Enterprise Linux 4, 5, and Red Hat Enterprise MRG via https://rhn.redhat.com/errata/RHSA-2010-0474.html, https://rhn.redhat.com/errata/RHSA-2009-1670.html and https://rhn.redhat.com/errata/RHSA-2009-1635.html respectively.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v2 Score Breakdown

Red HatNVDcve.org
Base Score7.27.8N/A
Attack VectorLocalNetworkN/A
Access ComplexityLowLowN/A
AuthenticationNoneNoneN/A
Confidentiality ImpactCompleteNoneN/A
Integrity ImpactCompleteNoneN/A
Availability ImpactCompleteCompleteN/A

Vector

Red Hat: AV:L/AC:L/Au:N/C:C/I:C/A:C

NVD: AV:N/AC:L/Au:N/C:N/I:N/A:C

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Crash, Exit, or Restart

NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.

Integrity,Confidentiality

Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory

In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.

Acknowledgements

Red Hat would like to thank Simon Vallet for reporting this issue.

Frequently Asked Questions

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