CVE-1999-1024: ip_print procedure in Tcpdump 3.4a allows remote attackers to cause a denial of service via a packet with a ze

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HIGH 7.5DOWNGRADE

CVE-1999-1024 is a high-severity flaw (CVSS 7.5) affecting tcpdump. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

ip_print procedure in Tcpdump 3.4a allows remote attackers to cause a denial of service via a packet with a zero length header, which causes an infinite loop and core dump when tcpdump prints the packet.

Why this priority

High severity
Public exploit reference

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	7.5 (High)
EPSS exploit chance	2.9% (top 13%)
CISA exploited list	No
Published	2001-11-28
Last modified	2026-09-25

Publisher (CNA): MITRE · Vendor: lbl

Last updated 2026-09-25 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2001-11-28 05:00 UTCPublished CVE record published
2026-09-25 20:10 UTCUpdated Record last modified

lbl tcpdump DOWNGRADE

Affected: 3.4

Fixed in: no fixed release known

Safe to downgrade to: a release before 3.4

1. Check installed version

apt-cache policy tcpdump || rpm -q tcpdump || tcpdump --version

2. No fixed release: DOWNGRADE to a release before 3.4 (Debian / Ubuntu)

apt-cache madison tcpdump sudo apt install tcpdump=<VERSION_BEFORE_3.4> sudo apt-mark hold tcpdump

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list tcpdump sudo dnf downgrade tcpdump-<VERSION_BEFORE_3.4> sudo dnf versionlock add tcpdump

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

Exploit-DB: tcpdump 3.4 - Protocol Four / Zero Header Length

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-1999-1024?

tcpdump: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-1999-1024 being exploited?

CVE-1999-1024 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-1999-1024 affect?

CVE-1999-1024 affects tcpdump. Severity is high (CVSS 7.5). ip_print procedure in Tcpdump 3.4a allows remote attackers to cause a denial of service via a packet with a zero length header, which causes an infinite loop and core dump when tcpdump prints the packet.

How urgent is CVE-1999-1024?

Priority 53/100. High severity; Public exploit reference

Related CVEs

CVE-2018-16301 HIGH 7.8 UPGRADE The command-line argument parser in tcpdump before 4.99.0 has a buffer overflow in tcpdump.c:read_infile()
CVE-2000-1026 HIGH 10.0 DOWNGRADE Multiple buffer overflows in LBNL tcpdump allow remote attackers to execute arbitrary commands.
CVE-2023-1801 MEDIUM 6.5 DOWNGRADE The SMB protocol decoder in tcpdump version 4.99.3 can perform an out-of-bounds write when decoding a crafted
CVE-2020-8037 HIGH 7.5 DOWNGRADE MITIGATE The ppp decapsulator in tcpdump 4.9.3 can be convinced to allocate a large amount of memory.
CVE-2020-8036 HIGH 7.5 DOWNGRADE The tok2strbuf() function in tcpdump 4.10.0-PRE-GIT was used by the SOME/IP dissector in an unsafe way.

References

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