RHSA-2012:0033 - Security Advisory

Topic

Updated php packages that fix several security issues are now available for
Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having moderate
security impact. Common Vulnerability Scoring System (CVSS) base scores,
which give detailed severity ratings, are available for each vulnerability
from the CVE links in the References section.

Description

PHP is an HTML-embedded scripting language commonly used with the Apache
HTTP Server.

It was found that the hashing routine used by PHP arrays was susceptible
to predictable hash collisions. If an HTTP POST request to a PHP
application contained many parameters whose names map to the same hash
value, a large amount of CPU time would be consumed. This flaw has been
mitigated by adding a new configuration directive, max_input_vars, that
limits the maximum number of parameters processed per request. By
default, max_input_vars is set to 1000. (CVE-2011-4885)

A use-after-free flaw was found in the PHP substr_replace() function. If a
PHP script used the same variable as multiple function arguments, a remote
attacker could possibly use this to crash the PHP interpreter or, possibly,
execute arbitrary code. (CVE-2011-1148)

An integer overflow flaw was found in the PHP exif extension. On 32-bit
systems, a specially-crafted image file could cause the PHP interpreter to
crash or disclose portions of its memory when a PHP script tries to extract
Exchangeable image file format (Exif) metadata from the image file.
(CVE-2011-4566)

An insufficient input validation flaw, leading to a buffer over-read, was
found in the PHP exif extension. A specially-crafted image file could cause
the PHP interpreter to crash when a PHP script tries to extract
Exchangeable image file format (Exif) metadata from the image file.
(CVE-2011-0708)

An integer overflow flaw was found in the PHP calendar extension. A remote
attacker able to make a PHP script call SdnToJulian() with a large value
could cause the PHP interpreter to crash. (CVE-2011-1466)

A bug in the PHP Streams component caused the PHP interpreter to crash if
an FTP wrapper connection was made through an HTTP proxy. A remote attacker
could possibly trigger this issue if a PHP script accepted an untrusted URL
to connect to. (CVE-2011-1469)

An off-by-one flaw was found in PHP. If an attacker uploaded a file with a
specially-crafted file name it could cause a PHP script to attempt to write
a file to the root (/) directory. By default, PHP runs as the "apache"
user, preventing it from writing to the root directory. (CVE-2011-2202)

Red Hat would like to thank oCERT for reporting CVE-2011-4885. oCERT
acknowledges Julian Walde and Alexander Klink as the original reporters of
CVE-2011-4885.

All php users should upgrade to these updated packages, which contain
backported patches to resolve these issues. After installing the updated
packages, the httpd daemon must be restarted for the update to take effect.

Solution

Before applying this update, make sure all previously-released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
https://access.redhat.com/kb/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 680972 - CVE-2011-0708 php: buffer over-read in Exif extension
• BZ - 688958 - CVE-2011-1148 php: use-after-free vulnerability in substr_replace()
• BZ - 689386 - CVE-2011-1466 php: Crash by converting serial day numbers (SDN) into Julian calendar
• BZ - 690905 - CVE-2011-1469 php: DoS when using HTTP proxy with the FTP wrapper
• BZ - 713194 - CVE-2011-2202 php: file path injection vulnerability in RFC1867 file upload filename
• BZ - 750547 - CVE-2011-4885 php: hash table collisions CPU usage DoS (oCERT-2011-003)
• BZ - 758413 - CVE-2011-4566 php: integer overflow in exif_process_IFD_TAG() may lead to DoS or arbitrary memory disclosure

CVEs

• CVE-2011-1148
• CVE-2011-0708
• CVE-2011-1469
• CVE-2011-2202
• CVE-2011-1466
• CVE-2011-4885
• CVE-2011-4566

References

• https://access.redhat.com/security/updates/classification/#moderate