SB2016111506 - Gentoo update for libpng

Description

This security bulletin contains information about 3 secuirty vulnerabilities.

1) Information disclosure (CVE-ID: CVE-2015-7981)

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to excessive data output by the application. A remote attacker can obtain sensitive process memory information via crafted tIME chunk data in an image file, which triggers an out-of-bounds read.

2) Buffer overflow (CVE-ID: CVE-2015-8126)

The vulnerability allows a remote non-authenticated attacker to read and manipulate data.

Multiple buffer overflows in the (1) png_set_PLTE and (2) png_get_PLTE functions in libpng before 1.0.64, 1.1.x and 1.2.x before 1.2.54, 1.3.x and 1.4.x before 1.4.17, 1.5.x before 1.5.24, and 1.6.x before 1.6.19 allow remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a small bit-depth value in an IHDR (aka image header) chunk in a PNG image.

3) Integer underflow (CVE-ID: CVE-2015-8540)

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to integer underflow within the png_check_keyword() function in pngwutil.c. A remote attacker can trick the victim to open a specially crafted PNG file, trigger an integer underflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Remediation

Install update from vendor's website.

References

• https://security.gentoo.org/glsa/201611-08