RHSA-2011:1423 - Security Advisory

Topic

Updated php53 and php packages that fix several security issues are now
available for Red Hat Enterprise Linux 5 and 6 respectively.

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.

A signedness issue was found in the way the PHP crypt() function handled
8-bit characters in passwords when using Blowfish hashing. Up to three
characters immediately preceding a non-ASCII character (one with the high
bit set) had no effect on the hash result, thus shortening the effective
password length. This made brute-force guessing more efficient as several
different passwords were hashed to the same value. (CVE-2011-2483)

Note: Due to the CVE-2011-2483 fix, after installing this update some users
may not be able to log in to PHP applications that hash passwords with
Blowfish using the PHP crypt() function. Refer to the upstream
"CRYPT_BLOWFISH security fix details" document, linked to in the
References, for details.

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)

Multiple memory leak flaws were found in the PHP OpenSSL extension. A
remote attacker able to make a PHP script use openssl_encrypt() or
openssl_decrypt() repeatedly could cause the PHP interpreter to use an
excessive amount of memory. (CVE-2011-1468)

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)

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 integer signedness issue was found in the PHP zip extension. An attacker
could use a specially-crafted ZIP archive to cause the PHP interpreter to
use an excessive amount of CPU time until the script execution time limit
is reached. (CVE-2011-1471)

A stack-based buffer overflow flaw was found in the way the PHP socket
extension handled long AF_UNIX socket addresses. An attacker able to make a
PHP script connect to a long AF_UNIX socket address could use this flaw to
crash the PHP interpreter. (CVE-2011-1938)

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)

All php53 and 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 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• 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 for x86_64 - Extended Update Support 6.1 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.1 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for IBM z Systems 6 s390x
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.1 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.1 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 i386
• Red Hat Virtual Storage Appliance (from RHUI) 6.1 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension (for IBM z Systems) 6 s390x

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 - 690899 - CVE-2011-1468 php: Multiple memory leaks in the OpenSSL extension
• BZ - 690905 - CVE-2011-1469 php: DoS when using HTTP proxy with the FTP wrapper
• BZ - 690915 - CVE-2011-1471 php: DoS (excessive CPU consumption) by processing certain Zip archive files
• BZ - 709067 - CVE-2011-1938 php: stack-based buffer overflow in socket_connect()
• BZ - 713194 - CVE-2011-2202 php: file path injection vulnerability in RFC1867 file upload filename
• BZ - 715025 - CVE-2011-2483 crypt_blowfish: 8-bit character mishandling allows different password pairs to produce the same hash

CVEs

• CVE-2011-2483
• CVE-2011-1148
• CVE-2011-1938
• CVE-2011-0708
• CVE-2011-1468
• CVE-2011-1469
• CVE-2011-1471
• CVE-2011-2202
• CVE-2011-1466

References

• https://access.redhat.com/security/updates/classification/#moderate
• http://www.php.net/security/crypt_blowfish.php