# CVE-2017-5203: tcpdump buffer overflow in BOOTP parser

Source: https://junglewise.ai/threats/cve-2017-5203-tcpdump-buffer-overflow-in-bootp-parser  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2017-01-28. Updated: 2026-05-13  
License: CC BY 4.0 with a link back

CVE-2017-5203 · Severity: critical · CVSS 9.8 · Published 2017-01-28

tcpdump is a widely used tool for monitoring and analyzing network traffic. A vulnerability in its BOOTP protocol parser allows an attacker to send specially crafted network packets that can cause the tool to crash or potentially execute unauthorized code. This could lead to a disruption of network monitoring operations or a compromise of the system running the tool.

## Quick answers

**Is CVE-2017-5203 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2017-5203 being exploited in the wild.

**How severe is CVE-2017-5203?** Critical severity, with a CVSS score of 9.8, published 28 January 2017.

**Which products and versions are affected?** tcpdump tcpdump before 4.9.0.

**Is there a fix for CVE-2017-5203?** A patch was published on 2017-01-29: Debian security update released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2017-5203 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2017-5203?** Check whether anything you run is named in the advisory. 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 vulnerability exists in tcpdump's BOOTP (Bootstrap Protocol) parser, specifically within the bootp_print() function in print-bootp.c. The flaw is triggered when tcpdump processes specially crafted BOOTP packets, either during live capture or when reading a malicious pcap file. Because the parser fails to properly validate the bounds of the input data, a remote attacker can cause a heap-based buffer overflow. This can result in a denial of service (application crash) or potentially the execution of arbitrary code with the privileges of the user running tcpdump. The vulnerability is addressed in version 4.9.0.

## Affected products

- tcpdump tcpdump before 4.9.0

## Timeline

- 2017-01-26: disclosed: Initial disclosure in Debian bug tracking system
- 2017-01-27: advisory: NVD publication date
- 2017-01-29: patched: Debian security update released

## References

- [http://www.debian.org/security/2017/dsa-3775](http://www.debian.org/security/2017/dsa-3775)
- [http://www.securityfocus.com/bid/95852](http://www.securityfocus.com/bid/95852)
- [http://www.securitytracker.com/id/1037755](http://www.securitytracker.com/id/1037755)
- [https://access.redhat.com/errata/RHSA-2017:1871](https://access.redhat.com/errata/RHSA-2017:1871)
- [https://security.gentoo.org/glsa/201702-30](https://security.gentoo.org/glsa/201702-30)
- [https://www.mail-archive.com/debian-bugs-dist%40lists.debian.org/msg1494526.html](https://www.mail-archive.com/debian-bugs-dist%40lists.debian.org/msg1494526.html)