dbcve.org
Debian LinuxOperating system · Debian

CVE-2017-5205

CRITICAL · 9.8 CVSS v3.0 Published 2017-01-28
Fix available
A fix is available. Upgrade to 4.9.0 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
The ISAKMP parser in tcpdump before 4.9.0 has a buffer overflow in print-isakmp.c:ikev2_e_print().

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A buffer overflow vulnerability exists in the ISAKMP parser of tcpdump versions prior to 4.9.0. The flaw is located in the ikev2_e_print() function within print-isakmp.c, where improper bounds checking during ISAKMP/IKEv2 packet parsing can lead to memory corruption. This vulnerability is remotely exploitable via crafted network packets, potentially allowing arbitrary code execution.

MitigationUpgrade tcpdump to version 4.9.0 or later to patch the buffer overflow in the ISAKMP parser. If upgrading is not immediately feasible, restrict network exposure of systems running tcpdump and disable packet parsing of untrusted ISAKMP traffic.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Debian LinuxOperating system
Affected:= 8.0= 9.0
Enterprise Linux DesktopOperating system
Affected:= 7.0
Enterprise Linux ServerOperating system
Affected:= 7.0
Enterprise Linux Server AusOperating system
Affected:= 7.4= 7.6
Enterprise Linux Server EusOperating system
Affected:= 7.4= 7.5= 7.6
Enterprise Linux Server TusOperating system
Affected:= 7.6
Enterprise Linux WorkstationOperating system
Affected:= 7.0
TcpdumpApplication
Affected:< 4.9.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check if tcpdump is installed
    Run 'which tcpdump' or 'dpkg -l | grep tcpdump' (Debian) or 'rpm -qa | grep tcpdump' (RHEL)
    Affected if tcpdump is not installed on the system (not affected)
  2. Determine the installed tcpdump version
    Run 'tcpdump --version' or 'tcpdump -V' and note the version number displayed
    Affected if The version shown is earlier than 4.9.0 (for example, 4.8.1, 4.7.4, etc.)
  3. Check the tcpdump package version via package manager
    Run 'apt-cache policy tcpdump' (Debian) or 'rpm -qi tcpdump' (RHEL) to get the exact packaged version
    Affected if The packaged version is earlier than 4.9.0
  4. Identify if tcpdump is used to capture ISAKMP/IKEv2 traffic
    Review any scripts, cron jobs, or systemd units that run tcpdump and examine if they capture network traffic that may contain ISAKMP/IKEv2 packets (typically UDP port 500 or 4500)
    Affected if tcpdump is actively processing or has processed ISAKMP/IKEv2 traffic on affected versions

You are affected if tcpdump version 4.9.0 or earlier is installed AND it is used to parse ISAKMP/IKEv2 network packets; otherwise, you are not affected.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 4.9.0 or later
Fixed in 4.9.0
Interim mitigation

Upgrade tcpdump to version 4.9.0 or later to patch the buffer overflow in the ISAKMP parser. If upgrading is not immediately feasible, restrict network exposure of systems running tcpdump and disable packet parsing of untrusted ISAKMP traffic.

Recommended fix High confidence

tcpdump 4.9.0 or later

  1. Identify the current tcpdump version using 'tcpdump --version' or 'rpm -q tcpdump'
  2. For Debian systems: Run 'apt-get update && apt-get install tcpdump' to upgrade to the latest version, which includes 4.9.0 or later
  3. For RHEL/CentOS systems: Run 'yum update tcpdump' or 'dnf update tcpdump' to apply the vendor security patch
  4. Verify the upgrade was successful by running 'tcpdump --version' and confirming version 4.9.0 or later is installed
  5. Test that network packet capture functionality continues to work as expected after the update
Caveat Minimal risk - this is a bug fix release addressing a critical security vulnerability; no known breaking changes for upgrading from earlier versions

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Debian Linux Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing3.0 h
  • Review / QA2.0 h
9.0 hours of engineering $1,570
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,512.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2017-5205 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2017-5205 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data