Bug 548876 (CVE-2009-4271) - CVE-2009-4271 kernel: 32bit process on 64bit system can trigger a kernel panic
Summary: CVE-2009-4271 kernel: 32bit process on 64bit system can trigger a kernel panic
Alias: CVE-2009-4271
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
Depends On: 549230 549231
TreeView+ depends on / blocked
Reported: 2009-12-18 22:32 UTC by Vincent Danen
Modified: 2023-05-11 13:53 UTC (History)
14 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Last Closed: 2013-03-15 04:01:05 UTC

Attachments (Terms of Use)

System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2010:0146 0 normal SHIPPED_LIVE Important: kernel security and bug fix update 2010-03-17 00:46:47 UTC

Description Vincent Danen 2009-12-18 22:32:48 UTC
A flaw was reported in the Linux kernel, versions 2.6.9 to 2.6.17, when running on x86_64, where a user could use a regular 32bit process to trigger a kernel panic, without any special privileges.  The bug occurs when a 32bit user process triggers a segfault (i.e. de-reference a null-pointer) after having performed a mprotect() to restrict any rwx access on its VDSO page.

In version 2.6.18 and on, the internal mechanism to access the VDSO uses the find_vma() wrapper which fixes the problem as a side-effect.

The reporter indicates that this only occurs on a 64bit machine with a program compiled in 32bit mode.


Red Hat would like to thank STMicroelectronics for responsibly reporting this issue.

Comment 14 errata-xmlrpc 2010-03-17 00:46:55 UTC
This issue has been addressed in following products:

  Red Hat Enterprise Linux 4

Via RHSA-2010:0146 https://rhn.redhat.com/errata/RHSA-2010-0146.html

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