#VU6663 Denial of service in Zlib - CVE-2016-9840

Vulnerability identifier: #VU6663

Vulnerability 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-2016-9840

CWE-ID: CWE-125

Exploitation vector: Network

Exploit availability: No

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

Vendor: GNU

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

The weakness exists in zlib due to out-of-bounds pointer arithmetic in inftrees.c. A remote attacker can send a specially crafted document, trick the victim into opening it, and cause the application to crash.

Successful exploitation of the vulnerability results in denial of service.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Zlib: 1.2.0 - 1.2.8

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External links
https://github.com/madler/zlib/commit/6a043145ca6e9c55184013841a67b2fef87e44c0
https://bugzilla.redhat.com/show_bug.cgi?id=1402345

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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.