Description
The rsvp_print function in tcpdump 3.9.1 and earlier allows remote attackers to cause a denial of service (infinite loop) via a crafted RSVP packet of length 4.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | tcpdump | 3.8.3-4 | — |
| Debian 13 | tcpdump | 3.8.3-4 | — |
| Debian 12 | tcpdump | 3.8.3-4 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 4 | arpwatch | 14:2.1a13-9.RHEL4 | RHSA-2005:417 |
| RHEL 4 | libpcap | 14:0.8.3-9.RHEL4 | RHSA-2005:417 |
| RHEL 4 | tcpdump | 14:3.8.2-9.RHEL4 | RHSA-2005:417 |
| RHEL 3 | libpcap | 14:0.7.2-7.E3.5 | RHSA-2005:421 |
| RHEL 3 | tcpdump | 14:3.7.2-7.E3.5 | RHSA-2005:421 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
Exploit-DB 1
- Ethereal 0.10.10 / tcpdump 3.9.1 - 'rsvp_print' Infinite Loop Denial of Service EDB-956 · dos · Apr 26, 2005 · verified
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 2
- RHSA-2005:421 Red Hat Security Advisory: tcpdump security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2005:417 Red Hat Security Advisory: tcpdump security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
References
- 20050426 tcpdump(/ethereal)[]: (RSVP) rsvp_print() infinite loop DOS. mailing-list
- 15125 third-party-advisory
- RHSA-2005:421 vendor-advisory
- oval:org.mitre.oval:def:10732 vdb-entry signature
- RHSA-2005:417 vendor-advisory
- FLSA:156139 vendor-advisory
- 18146 third-party-advisory
- 13390 vdb-entry