Red Hat Enterprise Linux 8 update for libxml2

1) Infinite loop

EUVDB-ID: #VU15364

Risk: Low

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2018-9251

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

Exploit availability: No

Description

The vulnerability allows a remote attacker to cause DoS condition on the target system.

The vulnerability exists in the xz_decomp() function of the GNOME libxml2 library, as defined in the xzlib.c source code due to an infinite loop condition in the Lempel-Ziv-Markov (LZMA) decompression feature during the processing of XML files. A remote unauthenticated attacker can trick the victim into opening a specially crafted XML file that submits malicious input, trigger an LZMA_MEMLIMIT_ERROR condition and cause the application to crash.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux for ARM 64: 8

Red Hat Enterprise Linux for Power, little endian: 8

Red Hat Enterprise Linux for IBM z Systems: 8

Red Hat Enterprise Linux for x86_64: 8.0

libxml2 (Red Hat package): before 2.9.7-7.el8

CPE2.3

• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_arm_64:8:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_little_endian:8:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_ibm_z_systems:8:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux:8.0:*:*:*:*:*:*:*
• cpe:2.3:a:red_hat:libxml2_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*

External links

https://access.redhat.com/errata/RHSA-2020:1827

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Null pointer dereference

EUVDB-ID: #VU13949

Risk: Low

CVSSv4.0: 5.5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/U:Clear]

CVE-ID: CVE-2018-14404

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

The vulnerability allows a remote attacker to cause DoS condition on the target system.

The vulnerability exists in the xmlXPathCompOpEval() function, as defined in the path.c source code file due to improper parsing of invalid XPath expressions in the XPATH_OP_AND and XPATH_OP_OR cases. A remote attacker can send a specially crafted request that submits malicious input to an application that is using the affected library, trigger a NULL pointer dereference and cause the application to crash.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux for ARM 64: 8

Red Hat Enterprise Linux for Power, little endian: 8

Red Hat Enterprise Linux for IBM z Systems: 8

Red Hat Enterprise Linux for x86_64: 8.0

libxml2 (Red Hat package): before 2.9.7-7.el8

CPE2.3

• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_arm_64:8:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_little_endian:8:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_ibm_z_systems:8:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux:8.0:*:*:*:*:*:*:*
• cpe:2.3:a:red_hat:libxml2_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*

External links

https://access.redhat.com/errata/RHSA-2020:1827

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.