Security Bulletin: Multiple vulnerabilities in IBM Java SDK affect IBM OS Images for Red Hat Linux Systems, IBM OS Images for AIX, and Windows. (CVE-2015-5041, CVE-2015-7575, CVE-2015-7981, CVE-2015-8126, CVE-2015-8472, and CVE-2015-8540)

Summary

There are multiple vulnerabilities in IBM® SDK Java™ Technology Edition, Version 6 and 7, that is used by IBM OS Images for Red Hat Linux Systems, AIX, and Windows. These issues were disclosed as part of the IBM Java SDK updates in January 2016 and includes the vulnerability commonly referred to as “SLOTH”.

Vulnerability Details

CVEID: CVE-2015-5041**
DESCRIPTION:** A flaw in the IBM J9 JVM allows code to invoke non-public interface methods under certain circumstances. Untrusted code could potentially exploit this. This could lead to sensitive data being exposed to an attacker, or the attacker being able to inject bad data.
CVSS Base Score: 4.8
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/106719 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N)

CVEID: CVE-2015-7575**
DESCRIPTION:** The TLS protocol could allow weaker than expected security caused by a collision attack when using the MD5 hash function for signing a ServerKeyExchange message during a TLS handshake. An attacker could exploit this vulnerability using man-in-the-middle techniques to impersonate a TLS server and obtain credentials. This vulnerability is commonly referred to as “SLOTH”.
CVSS Base Score: 7.1
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/109415 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:R/UI:U/C:H/I:L/A:N)

CVEID: CVE-2015-7981**
DESCRIPTION:** libpng could allow a remote attacker to obtain sensitive information, caused by an out-of-bounds read in the png_convert_to_rfc1123 function. An attacker could exploit this vulnerability to obtain sensitive information.
CVSS Base Score: 5.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/107740 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)

CVEID: CVE-2015-8126**
DESCRIPTION:** libpng is vulnerable to a buffer overflow, caused by improper bounds checking by the png_set_PLTE() and png_get_PLTE() functions. By persuading a victim to open a specially-crafted PNG file, a remote attacker could overflow a buffer and execute arbitrary code on the system.
CVSS Base Score: 7.8
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/108010 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:R/UI:U/C:H/I:H/A:H)

CVEID: CVE-2015-8472**
DESCRIPTION:** libpng is vulnerable to a buffer overflow, caused by improper bounds checking by the png_get_PLTE() and png_set_PLTE() functions. By persuading a victim to open a specially crafted PNG image, a remote attacker could overflow a buffer and execute arbitrary code on the system or cause the application to crash.
CVSS Base Score: 6.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/109392 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:R/UI:U/C:L/I:L/A:L)

CVEID: CVE-2015-8540**
DESCRIPTION:** libpng is vulnerable to a buffer overflow, caused by a read underflow in png_check_keyword in pngwutil.c. By sending an overly long argument, a remote attacker could overflow a buffer and execute arbitrary code on the system or cause the application to crash.
CVSS Base Score: 9.8
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/109219 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)

Affected Products and Versions

IBM OS Image for Red Hat Linux Systems 3.0.0.0 and earlier.
IBM OS Image for AIX Systems 2.1.1.0 and earlier.

Remediation/Fixes

Virtual machines deployed from IBM PureApplication Systems are affected. This includes RedHat Linux, AIX-based, and Windows-based deployments. The solution is to apply the following IBM PureApplication System fix to the deployed virtual machines.

Java Update for Windows
http://www-933.ibm.com/support/fixcentral/swg/selectFixes?parent=PureSystems&product=ibm/WebSphere/PureApplication+System&platform=All&function=fixId&fixids=Java_Update_Windows_Feb_2016_ _

Java Update for Linux
http://www-933.ibm.com/support/fixcentral/swg/selectFixes?parent=PureSystems&product=ibm/WebSphere/PureApplication+System&platform=All&function=fixId&fixids=Java_Update_Linux_Feb_2016_ _

Java Update for AIX
http://www-933.ibm.com/support/fixcentral/swg/selectFixes?parent=PureSystems&product=ibm/WebSphere/PureApplication+System&platform=All&function=fixId&fixids=Java_Update_AIX_Feb_2016_ _

1. Import the fix into the Emergency Fix catalogue.
2. For deployed instances, apply this emergency fix on the VM.
3. Restart the deployed instance after the fix is applied.

Workarounds and Mitigations

For CVE-2015-7575:

Users of Java 7 and later can address the issue by updating the /jre/lib/security/java.security file as follows (both steps are required):

· Add MD5 to the jdk.certpath.disabledAlgorithms property - e.g. jdk.certpath.disabledAlgorithms=MD2, RSA keySize < 1024, MD5

· Add MD5withRSA to the jdk.tls.disabledAlgorithms property - e.g. jdk.tls.disabledAlgorithms=SSLv3, RC4, DH keySize < 768, MD5withRSA

Java 6 requires code changes in the JSSE component in addition to the java.security file modifications, so upgrading the JDK is the only solution.