OpenBSD 7.4 pf state race condition kernel crash

published 2024-03-01 2 y ago modified 2026-06-17 4 mo ago also EUVD-2023-57180

cvss: 6.2; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.1%; EPSS 0.1% chance of exploitation in 30 days, percentile 3%
public exploits: 0; none known

In OpenBSD 7.4 before errata 009, a race condition between pf(4)'s processing of packets and expiration of packet states may cause a kernel panic.

Patch / fix

fixed in 1 links 2

OpenBSD OpenBSD 7.4 errata 009

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 y ago (2024-03-01)

Exploit prediction

0.14% chance of exploitation in the next 30 days, higher than 3% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	6.2	CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA	3.1	6.2	CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

OpenBSD OpenBSD

Classification

Weakness

CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition

References

Sources

CVE List CVE-2023-52556
NVD CVE-2023-52556

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary