CVE-2009-1895: Null Pointer Dereference

Published Jul 16, 2009
·
Updated

The personality subsystem in the Linux kernel before 2.6.31-rc3 has a PERCLEARONSETID setting that does not clear the ADDRCOMPATLAYOUT and MMAPPAGEZERO flags when executing a setuid or setgid program, which makes it easier for local users to leverage the details of memory usage to (1) conduct NULL pointer dereference attacks, (2) bypass the mmapminaddr protection mechanism, or (3) defeat address space layout randomization (ASLR).

Affected Software

9 affected components
Linux Linux kernel<=2.6.31
Linux Linux kernel=2.6.31-rc1
Linux Linux kernel=2.6.31-rc2
Debian Debian Linux=5.0
Debian Debian Linux=4.0
Canonical Ubuntu Linux=6.06
Canonical Ubuntu Linux=9.04
Canonical Ubuntu Linux=8.04
Canonical Ubuntu Linux=8.10

Event History

Jul 16, 2009
CVE Published
via MITRE·03:00 PM
Data Sourced
via MITRE·03:00 PM
Description
Feb 17, 2026
Data Sourced
via Launchpad·07:46 PM
Description

Frequently Asked Questions

1

What is the severity of CVE-2009-1895?

CVE-2009-1895 is classified as a moderate severity vulnerability.

2

How do I fix CVE-2009-1895?

To fix CVE-2009-1895, update the Linux kernel to version 2.6.31 or newer.

3

Which systems are affected by CVE-2009-1895?

CVE-2009-1895 affects Linux kernel versions prior to 2.6.31, as well as specific versions of Debian and Ubuntu.

4

What type of vulnerability is CVE-2009-1895?

CVE-2009-1895 is a local privilege escalation vulnerability in the Linux kernel's personality subsystem.

5

What happens if CVE-2009-1895 is exploited?

Exploitation of CVE-2009-1895 can allow local users to gain elevated privileges.

Contact

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