#VU9689 Heap-based buffer over-read in Libxml2 - CVE-2017-9050

Vulnerability identifier: #VU9689

Vulnerability 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-2017-9050

CWE-ID: CWE-126

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Libxml2
Universal components / Libraries / Libraries used by multiple products

Vendor: Gnome Development Team

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

The weakness exists in the xmlDictAddString function of XMLSoft libxml2 due to improper bounds checking in the dict.c code. A remote attacker can send a specially crafted request, trigger heap-based buffer over-read condition and cause the service to crash.

Successful exploitation of the vulnerability results in denial of service.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Libxml2: 2.9.4

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External links
https://www.vuxml.org/freebsd/76e59f55-4f7a-4887-bcb0-11604004163a.html

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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.