# CVE-2016-5323: LibTIFF divide by zero in _TIFFFax3fillruns

Source: https://junglewise.ai/threats/cve-2016-5323-libtiff-divide-by-zero-in-tifffax3fillruns  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2017-01-20. Updated: 2026-05-13  
License: CC BY 4.0 with a link back

CVE-2016-5323 · Severity: high · CVSS 7.5 · Published 2017-01-20

LibTIFF is a widely used library for processing TIFF image files in various applications and operating systems. A vulnerability exists that allows a remote attacker to crash applications using this library by providing a specially crafted image file. This results in a denial of service, potentially disrupting business operations that rely on automated image processing or document management.

Technologies: [Libtiff](https://junglewise.ai/threats/technologies/libtiff), [Opensuse](https://junglewise.ai/threats/technologies/opensuse). Vendors: [Libtiff](https://junglewise.ai/threats/vendors/libtiff), [Opensuse](https://junglewise.ai/threats/vendors/opensuse).

## Quick answers

**Is CVE-2016-5323 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2016-5323 being exploited in the wild.

**How severe is CVE-2016-5323?** High severity, with a CVSS score of 7.5, published 20 January 2017.

**Which products and versions are affected?** LibTIFF libtiff before 4.0.6.

**Is there a fix for CVE-2016-5323?** A patch was published on 2017-01-13: Debian released security updates for jessie and sid Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2016-5323 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2016-5323?** Check whether you run Libtiff or Opensuse. 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 divide-by-zero vulnerability exists in the _TIFFFax3fillruns function within tif_fax3.c of libtiff. The flaw is triggered when the library processes a specially crafted TIFF image, specifically when using tools like tiffcrop that invoke Fax3 decoding routines. An attacker can exploit this by providing a malicious image file to an application linked against libtiff, leading to an arithmetic exception and subsequent process crash. This is a remote, unauthenticated attack vector requiring no user interaction beyond the application attempting to process the file. The issue was addressed in libtiff version 4.0.6 and later.

## Affected products

- LibTIFF libtiff before 4.0.6

## Timeline

- 2016-06-15: disclosed: Public disclosure on oss-security mailing list
- 2017-01-09: advisory: Gentoo security advisory released
- 2017-01-13: patched: Debian released security updates for jessie and sid
- 2017-01-20: advisory: NVD publication date

## References

- [http://lists.opensuse.org/opensuse-security-announce/2016-12/msg00017.html](http://lists.opensuse.org/opensuse-security-announce/2016-12/msg00017.html)
- [http://www.debian.org/security/2017/dsa-3762](http://www.debian.org/security/2017/dsa-3762)
- [http://www.openwall.com/lists/oss-security/2016/06/15/6](http://www.openwall.com/lists/oss-security/2016/06/15/6)
- [http://www.securityfocus.com/bid/91196](http://www.securityfocus.com/bid/91196)
- [https://security.gentoo.org/glsa/201701-16](https://security.gentoo.org/glsa/201701-16)

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