Description
arch/x86/ia32/ia32entry.S in the Linux kernel before 2.6.31.4 on the x86_64 platform does not clear certain kernel registers before a return to user mode, which allows local users to read register values from an earlier process by switching an ia32 process to 64-bit mode.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 5.0 | linux-2.6 | 2.6.26-19lenny1 | DSA-1915-1 |
| Debian 4.0 | linux-2.6.24 | 2.6.24-6~etchnhalf.9etch1 | DSA-1928-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 5 | kernel +11 | 2.6.18-164.11.1.el5 | RHSA-2010:0046 |
| RHEL 4 | kernel +10 | 2.6.9-89.0.18.EL | RHSA-2009:1671 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat MRG 1 | kernel-rt +9 | 2.6.24.7-137.el5rt | RHSA-2009:1540 |
Advisories 5
- RHSA-2010:0046 Red Hat Security Advisory: kernel security and bug fix update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2009:1671 Red Hat Security Advisory: kernel security and bug fix update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2009:1540 Red Hat Security Advisory: kernel-rt security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- DSA-1915-1 linux-2.6 - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-1928-1 linux-2.6.24 - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
References
- http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.31.4
- RHSA-2009:1671 vendor-advisory
- http://git.kernel.org/?p=linux/kernel/git/x86/linux-2.6-tip.git%3Ba=commit%3Bh=24e35800cdc4350fc34e2bed37b608a9e13ab3b6
- RHSA-2009:1540 vendor-advisory
- USN-864-1 vendor-advisory
- 36927 third-party-advisory
- oval:org.mitre.oval:def:7359 vdb-entry signature
- 37351 third-party-advisory
- 37075 third-party-advisory
- http://support.avaya.com/css/P8/documents/100073666
- SUSE-SA:2009:056 vendor-advisory
- SUSE-SA:2010:012 vendor-advisory
- [oss-security] 20091001 Re: CVE Request (kernel) mailing-list
- https://bugzilla.redhat.com/show_bug.cgi?id=526788
- oval:org.mitre.oval:def:10823 vdb-entry signature
- 36576 vdb-entry
- [oss-security] 20091002 Re: CVE Request (kernel) mailing-list
- [oss-security] 20091009 Re: CVE Request (kernel) mailing-list
- [oss-security] 20091001 CVE Request (kernel) mailing-list
- FEDORA-2009-10525 vendor-advisory
- RHSA-2010:0095 vendor-advisory
- RHSA-2010:0046 vendor-advisory
- [linux-kernel] 20091001 [tip:x86/urgent] x86: Don't leak 64-bit kernel register values to 32-bit processes mailing-list
- SUSE-SA:2009:054 vendor-advisory