CRITICAL

CVE-2019-5597

CVSS v3

9.1

CRITICAL

EPSS Score

3.7 %

exploit probability, as of 2026-10-19

CISA KEV

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Neither OSV.dev nor the vendor advisories we read list affected versions for CVE-2019-5597 yet.

Full record on NVD

Description

In FreeBSD 11.3-PRERELEASE and 12.0-STABLE before r347591, 11.2-RELEASE before 11.2-RELEASE-p10, and 12.0-RELEASE before 12.0-RELEASE-p4, a bug in the pf IPv6 fragment reassembly logic incorrectly uses the last extension header offset from the last received packet instead of the first packet allowing maliciously crafted IPv6 packets to cause a crash or potentially bypass the packet filter.

Technical details

Published: 2019-05-15

Frequently asked questions

What is CVE-2019-5597?

Is CVE-2019-5597 actively exploited?

Active exploitation of CVE-2019-5597 has not been confirmed. Its EPSS score was 3.7% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2019-5597?

CVE-2019-5597 has a CVSS v3 base score of 9.1 (CRITICAL severity).

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