TITLE:
FreeBSD FPU x87 Register Information Leak

SECUNIA ADVISORY ID:
SA19715

VERIFY ADVISORY:
http://secunia.com/advisories/19715/

CRITICAL:
Not critical

IMPACT:
Exposure of sensitive information

WHERE:
Local system

OPERATING SYSTEM:
FreeBSD 6.x
http://secunia.com/product/6778/
FreeBSD 5.x
http://secunia.com/product/1132/
FreeBSD 4.x
http://secunia.com/product/139/

DESCRIPTION:
A security issue has been reported in FreeBSD, which can be exploited
by malicious, local users to gain knowledge of potentially sensitive
information.

The problem is caused due to AMD K7/K8 CPUs only saving/restoring
certain x87 registers in FXSAVE instructions when an exception is
pending. This may leak x87 register information between processes.

SOLUTION:
Update to a fixed version or apply patch.

Fixed versions:
2006-04-19 07:00:35 UTC (RELENG_6, 6.1-STABLE)
2006-04-19 07:00:50 UTC (RELENG_6_1, 6.1-RELEASE)
2006-04-19 07:01:12 UTC (RELENG_6_0, 6.0-RELEASE-p7)
2006-04-19 07:01:30 UTC (RELENG_5, 5.5-STABLE)
2006-04-19 07:01:53 UTC (RELENG_5_4, 5.4-RELEASE-p14)
2006-04-19 07:02:23 UTC (RELENG_5_3, 5.3-RELEASE-p29)
2006-04-19 07:02:43 UTC (RELENG_4, 4.11-STABLE)
2006-04-19 07:03:01 UTC (RELENG_4_11, 4.11-RELEASE-p17)
2006-04-19 07:03:14 UTC (RELENG_4_10, 4.10-RELEASE-p23)

Patch for FreeBSD 4.10 and 4.11:
ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-06:14/fpu4x.patch
ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-06:14/fpu4x.patch.asc

Patch for FreeBSD 5.3, 5.4, and 6.0:
ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-06:14/fpu.patch
ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-06:14/fpu.patch.asc

PROVIDED AND/OR DISCOVERED BY:
The vendor credits Jan Beulich.

ORIGINAL ADVISORY:
ftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-06:14.fpu.asc

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About:
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Please Note:
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Secunia NEVER sends attached files with advisories.
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