CVE-2023-6534

highpriority · track · 30EPSS 0.007 · 54 %ileDEEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.74% (54th) EPSS
CVSS 7.5 · high
Is it mine?
9 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

In versions of FreeBSD 14.0-RELEASE before 14-RELEASE-p2, FreeBSD 13.2-RELEASE before 13.2-RELEASE-p7 and FreeBSD 12.4-RELEASE before 12.4-RELEASE-p9, the pf(4) packet filter incorrectly validates TCP sequence numbers.  This could allow a malicious actor to execute a denial-of-service attack against hosts behind the firewall.

01

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6
v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-284US
03

affected products (9)

Products and version ranges known to be affected.

04

advisories (1)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2023-3061FreeBSD OS: Schwachstelle ermöglicht Denial of ServiceDeutsch2023-12-05csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann eine Schwachstelle in FreeBSD OS ausnutzen, um einen Denial of Service Angriff durchzuführen.

05

also known as (4)

Other names and identifiers for this entity.

06

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bdunvdcert_bundNVDCVE.orgMITRE
published 2023-12-13modified 2026-06-17
07

references (7)

External citations — patches, advisories, analysis.

scry

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