Description
In OpenBSD through 7.8, the slaacd and rad daemons have an infinite loop when they receive a crafted ICMPv6 Neighbor Discovery (ND) option (over a local network) with length zero, because of an "nd_opt_len * 8 - 2" expression with no preceding check for whether nd_opt_len is zero.
Affected products
openbsd: openbsd
References3
- github.com/openbsd/src/commit/086c5738bcd3c203bcc08d024fcf983cb… Patch
- www.openbsd.org/errata78.html ProductRelease Notes
- www.rfc-editor.org/rfc/rfc4861#section-4.6 Not Applicable
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - EPSS — exploit probability
- 0% percentile: 11 · as of 13 November 2026
- CWE
- CWE-1284CWE-835
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