SARA / Free Tools / CVE / CVE-2023-6399

CVE-2023-6399 — A format string vulnerability in Zyxel ATP series firmware versions from 4

A format string vulnerability in Zyxel ATP series firmware versions from 4.32 through 5.37 Patch 1, USG FLEX series firmware versions from 4.50 through 5.37 Patch 1, USG FLEX 50(W) series firmware versions from 4.16 through 5.37 Patch 1, USG20(W)-VPN series firmware versions from

CVSS
5.7 MEDIUM
EPSS
0.31% (top 46.50%)
CWE
CWE-134
Published
2024-02-20T01:42:21.027Z
Last modified
2024-08-02T08:28:21.797Z
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

01What is this vulnerability?

A format string vulnerability in Zyxel ATP series firmware versions from 4.32 through 5.37 Patch 1, USG FLEX series firmware versions from 4.50 through 5.37 Patch 1, USG FLEX 50(W) series firmware versions from 4.16 through 5.37 Patch 1, USG20(W)-VPN series firmware versions from 4.16 through 5.37 Patch 1, and USG FLEX H series firmware versions from 1.10 through 1.10 Patch 1 could allow an…

02Affected products

VendorProductVersions
ZyxelATP series firmwareversion 4.32 through 5.37 Patch 1
ZyxelUSG FLEX series firmwareversion 4.50 through 5.37 Patch 1
ZyxelUSG FLEX 50(W) series firmwareversion 4.16 through 5.37 Patch 1
ZyxelUSG20(W)VPN series firmware — version 4.16 through 5.37 Patch 1
ZyxelUSG FLEX H series firmwareversion 1.10 through 1.10 Patch 1

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

09References

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