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PatchSiren cyber security CVE debrief

CVE-2016-7938 Tcpdump CVE debrief

CVE-2016-7938 is a critical tcpdump flaw in the ZeroMQ parser. The vulnerable code path, print-zeromq.c:zmtp1_print_frame(), can hit an integer overflow while parsing frame data. NVD rates the issue 9.8/Critical with the usual high-impact triad: remote attack vector, no privileges, no user interaction, and potential high confidentiality, integrity, and availability impact. The CVE description says the issue affects tcpdump before 4.9.0.

Vendor
Tcpdump
Product
Unknown
CVSS
CRITICAL 9.8
CISA KEV
Not listed in stored evidence
Original CVE published
2017-01-28
Original CVE updated
2026-05-13
Advisory published
2017-01-28
Advisory updated
2026-05-13

Who should care

Security teams, distro maintainers, and operators who deploy tcpdump for packet inspection or analysis should care most. This also matters for appliances, monitoring systems, and automated pipelines that may process untrusted capture data.

Technical summary

The vulnerability is an integer overflow (CWE-190) in tcpdump’s ZeroMQ parser, specifically in print-zeromq.c:zmtp1_print_frame(). According to the CVE description, tcpdump versions before 4.9.0 are affected. NVD also lists a vulnerable CPE range for tcpdump through 4.8.1. The record’s CVSS 3.0 vector is AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, indicating that a remotely reachable parsing flaw can have severe impact when malformed input is processed.

Defensive priority

High. Parsing bugs in packet-analysis tools are worth prompt remediation because they may be triggered by malicious or malformed network traffic or capture files, and tcpdump is often used in operational or investigative workflows.

Recommended defensive actions

  • Upgrade tcpdump to a fixed release at or above 4.9.0, or apply the vendor/distribution package that includes the backported fix.
  • Check Debian, Red Hat, and Gentoo security advisories for the patched package version used in your environment.
  • Inventory systems that use tcpdump in automated jobs, capture analysis, or monitoring appliances, and prioritize those exposed to untrusted traffic or files.
  • Restrict privilege and isolate packet-processing workflows where possible so a parser failure has less operational impact.
  • Validate that your software asset inventory distinguishes installed package versions from upstream release versions before closing the issue.

Evidence notes

This debrief is based on the supplied CVE record and official/adjacent references in the source corpus: the CVE description identifies an integer overflow in print-zeromq.c:zmtp1_print_frame(), the NVD record maps the weakness to CWE-190, and the referenced advisories include Debian DSA-3775, Red Hat RHSA-2017:1871, and Gentoo GLSA 201702-30. The timeline uses the CVE publishedAt date supplied in the corpus; the later modifiedAt date is noted only as record metadata.

Sources and references

Verified primary and authoritative sources

  • CVE-2016-7938 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2016-7938

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2016-7938 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2016-7938

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.