Is CVE-2016-9844 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2016-9844 being exploited in the wild.

How severe is CVE-2016-9844?

Medium severity, with a CVSS score of 4, published 18 January 2017.

Is there a fix for CVE-2016-9844?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2016-9844 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2016-9844?

Check whether you run Unzip Project Unzip. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2016-9844: Info-ZIP UnZip buffer overflow in zi_short function

CVE-2016-9844 · Severity: medium · CVSS 4 · Published 2017-01-18

A vulnerability in the Info-ZIP UnZip utility, a common tool for extracting compressed files, could allow an attacker to crash the application. By providing a specially crafted ZIP file with a large compression method value, an attacker can trigger a buffer overflow. This results in a denial-of-service condition where the tool fails to process the file and terminates unexpectedly.

Technologies: Unzip Project Unzip. Vendors: Unzip Project.

Quick answers

Is CVE-2016-9844 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2016-9844 being exploited in the wild.
How severe is CVE-2016-9844?: Medium severity, with a CVSS score of 4, published 18 January 2017.
Which products and versions are affected?: Info-ZIP UnZip 6.0.
Is there a fix for CVE-2016-9844?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2016-9844 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2016-9844?: Check whether you run Unzip Project Unzip. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A buffer overflow exists in Info-ZIP UnZip 6.0 within the zi_short() function in zipinfo.c. The vulnerability is triggered when the two-byte compression method field in a ZIP file's central directory file header contains a value greater than 999. The code uses sprintf() to write this value into a 5-byte buffer (methbuf) starting at an offset of 1 byte. When the value is 1000 or greater, the resulting string (including the null terminator) exceeds the buffer bounds. This is a local attack vector requiring the victim to process a malicious ZIP file using the zipinfo tool. A fix was proposed for version 6.1e beta.

Affected products

Info-ZIP UnZip 6.0

Timeline

2016-11-22: disclosed: Vulnerability reported to Ubuntu by Alexis Vanden Eijnde.
2016-12-05: other: CVE-2016-9844 assigned.
2017-01-18: advisory: NVD published the vulnerability.

References

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