CVE-2018-17156

Severity: medium (CVSS 5.9 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2018-11-28 · updated 2026-06-17
Weakness: CWE-787

Description

In FreeBSD before 11.2-STABLE(r340268) and 11.2-RELEASE-p5, due to incorrectly accounting for padding on 64-bit platforms, a buffer underwrite could occur when constructing an ICMP reply packet when using a non-standard value for the net.inet.icmp.quotelen sysctl.

Affected products

FreeBSD: before 11.2; 11.2-p5 — fixed in 11.2

How to fix

Upgrade to a fixed version: FreeBSD 11.2. Check the vendor advisory for mitigations.

References

http://www.securityfocus.com/bid/106052
https://security.freebsd.org/advisories/FreeBSD-EN-18:13.icmp.asc
http://www.securityfocus.com/bid/106052
https://security.freebsd.org/advisories/FreeBSD-EN-18:13.icmp.asc

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