What is CVE-2022-27881?

CVE-2022-27881 is a high-severity vulnerability in OpenBSD, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 7.5/10. Published 2022-03-25.

How severe is CVE-2022-27881?

High severity. CVSS v3 base score is 7.5 out of 10.

Buffer overflow in OpenBSD

CVE-2022-27881

engine.c in slaacd in OpenBSD 6.9 and 7.0 before 2022-02-21 has a buffer overflow triggerable by an IPv6 router advertisement with more than seven nameservers. NOTE: privilege separation and pledge can prevent exploitation.

Vulnerability class: Buffer Overflow

Published 2022-03-25 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.019 (78.8th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 79th percentile — 78.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.019 · newest: 0.019 · change: 0.000

Affected products

OpenBSD — versions 6.9, 7.0

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

ftp.openbsd.org/pub/OpenBSD/patches/7.0/common/014_slaacd.patch.sig (Patch, Release Notes, Vendor Advisory)
blog.quarkslab.com/heap-overflow-in-openbsds-slaacd-via-router-advertisement.ht… (Exploit, Patch, Third Party Advisory)
ftp.openbsd.org/pub/OpenBSD/patches/6.9/common/030_slaacd.patch.sig (Patch, Release Notes, Vendor Advisory)
security.netapp.com/advisory/ntap-20220506-0005/ (Third Party Advisory)

Frequently asked questions

What is CVE-2022-27881?: CVE-2022-27881 is a high-severity vulnerability in OpenBSD, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 7.5/10. Published 2022-03-25.
How severe is CVE-2022-27881?: High severity. CVSS v3 base score is 7.5 out of 10.