Apple Computer Inc. Information for VU#388984

libpng fails to properly check length of transparency chunk (tRNS) data

Status

Affected

Vendor Statement

APPLE-SA-2004-09-09 Mac OS X 10.3.5

Mac OS X 10.3.5 is now available and delivers security enhancements
for the following components:

Component: libpng (Portable Network Graphics)
CVE-IDs: CAN-2002-1363, CAN-2004-0421, CAN-2004-0597,
CAN-2004-0598, CAN-2004-0599
Impact: Malicious png images can cause application crashes and could
execute arbitrary code

Description: A number of buffer overflows, null pointer dereferences
and integer overflows have been discovered in the reference library
for reading and writing PNG images. These vulnerabilities have been
corrected in libpng which is used by the CoreGraphics and AppKit
frameworks in Mac OS X. After installing this update, applications
that use the PNG image format via these frameworks will be protected
against these flaws.

Note: The libpng security fixes are also available separately for Mac
OS X 10.3.4 and Mac OS X 10.2.8 via Security Update 2004-08-09.

==================

Component: Safari
CVE ID: CAN-2004-0743
Impact: In a special situation, navigation using the forward/backward
buttons can re-send form data to a GET url.

Description: This is for a situation where a web form is sent to a
server using a POST method which issues an HTTP redirect to a GET
method url. Using the forward/backward buttons will cause Safari to
re-POST the form data to the GET url. Safari has been modified so
that in this situation forward/backward navigation will result in only
a GET method.

==================

Component: TCP/IP Networking
CVE ID: CAN-2004-0744
Impact: Maliciously crafted IP fragments can use too many system
resources preventing normal network operation.

Description: The "Rose Attack" describes a specially constructed
sequence of IP fragments designed to consume system resources. The
TCP/IP implementation has been modified to limit the resources
consumed and prevents this denial of service attack.

================================================

Mac OS X 10.3.5 may be obtained from the Software Update
pane in System Preferences, or Apple's Software Downloads web site:
http://www.apple.com/support/downloads/

Information will also be posted to the Apple Product Security
web site:
http://www.apple.com/support/security/security_updates.html

This message is signed with Apple's Product Security PGP key,
and details are available at:
http://www.apple.com/support/security/security_pgp.html

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Vendor References

None

Addendum

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