Security Bulletin: Multiple vulnerabilities in libxml2 affect PowerKVM

Summary

PowerKVM is affected by several vulnerabilities in libxml2. These vulnerabilities are now fixed.

Vulnerability Details

CVEID: CVE-2015-1819**
DESCRIPTION:** Libxml is vulnerable to a denial of service, caused by an XML External Entity Injection (XXE) error in the xmlreader when processing XML data. A remote attacker could exploit this vulnerability to consume all available memory resources.
CVSS Base Score: 5.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/107272 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)

CVEID: CVE-2015-5312**
DESCRIPTION:** An unspecified error in Libxml2 related to an entity expansion flaw has an unknown impact and attack vector.
CVSS Base Score: 5.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/108319 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)

CVEID: CVE-2015-7497**
DESCRIPTION:** Libxml2 is vulnerable to a denial of service, caused by a heap-based buffer overflow in the xmlDictComputeFastQKey() function. A remote attacker could exploit this vulnerability to cause a denial of service.
CVSS Base Score: 5.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/108320 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)

CVEID: CVE-2015-7498**
DESCRIPTION:** An unspecified error in Libxml2 related to the processing of entities after encoding conversion failures have occured has an unknown impact and attack vector.
CVSS Base Score: 5.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/108321 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)

CVEID: CVE-2015-7499**
DESCRIPTION:** An unspecified error in Libxml2 related to some parser errors has an unknown impact and attack vector.
CVSS Base Score: 5.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/108322 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)

CVEID: CVE-2015-7500**
DESCRIPTION:** Libxml2 is vulnerable to a denial of service, caused by a memory access error when handling invalid entity boundaries. A remote attacker could exploit this vulnerability to cause a denial of service.
CVSS Base Score: 5.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/108323 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)

CVEID: CVE-2015-7941**
DESCRIPTION:** Libxml2 is vulnerable to a denial of service, caused by a heap-based buffer overflow in the xmlParseEntityDecl or xmlParseConditionalSections function. By using specially-crafted XML data, a remote attacker could exploit this vulnerability to trigger an out-of-bounds read and cause the system to crash.
CVSS Base Score: 4.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/108071 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L)

CVEID: CVE-2015-7942**
DESCRIPTION:** Libxml2 is vulnerable to a denial of service, caused by a heap-based buffer overflow in the xmlParseConditionalSections function. By using specially-crafted XML data, a remote attacker could exploit this vulnerability to trigger an out-of-bounds read and cause the system to crash.
CVSS Base Score: 4.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/108073 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L)

CVEID: CVE-2015-8241**
DESCRIPTION:** libxml2 is vulnerable to a buffer overflow, caused by improper bounds checking by the XML parser in xmlNextChar. By using a malformed XML file, a local attacker could overflow a buffer and execute arbitrary code on the system or cause the application to crash.
CVSS Base Score: 5.9
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/108169 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L)

CVEID: CVE-2015-8242**
DESCRIPTION:** libxml2 is vulnerable to a stack-based buffer overflow, caused by improper bounds checking by the HTML parser in push mode in xmlSAX2TextNode. By using a malformed XML file, a local attacker could overflow a buffer and execute arbitrary code on the system or cause the application to crash.
CVSS Base Score: 5.9
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/108170 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L)

CVEID: CVE-2015-8317**
DESCRIPTION:** libxml2 is vulnerable to a heap-based buffer overflow, caused by improper bounds checking by the xmlParseXMLDecl function. By using a malformed XML file, a local attacker could overflow a buffer and execute arbitrary code on the system or cause the application to crash.
CVSS Base Score: 5.9
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/108316 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L)

Affected Products and Versions

PowerKVM 2.1 and PowerKVM 3.1

Remediation/Fixes

Customers can update PowerKVM systems by using “yum update”.

Fix images are made available via Fix Central. For version 3.1, see https://ibm.biz/BdHggw for 3.1 service build 3 or later.

For version 2.1, the fix is made available via Fix Central (https://ibm.biz/BdEnT8) in 2.1.1 Build 65.6 and all later 2.1.1 SP3 service builds and 2.1.1 service packs. Customers running v2.1 are, in any case, encouraged to upgrade to v3.1.

For v2.1 systems currently running fix levels of PowerKVM prior to 2.1.1, please see <http://download4.boulder.ibm.com/sar/CMA/OSA/05e4c/0/README&gt; for prerequisite fixes and instructions.

Workarounds and Mitigations

v2.1 customers can work around the problem by upgrading to the fixed release of v3.1