CVE-2023-6397

mediumpriority · track · 21EPSS 0.003 · 23 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.30% (23rd) EPSS

CVSS 5.3 · medium

Is it mine?

42 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

A null pointer dereference vulnerability in Zyxel ATP series firmware versions from 4.32 through 5.37 Patch 1 and USG FLEX series firmware versions from 4.50 through 5.37 Patch 1 could allow a LAN-based attacker to cause denial-of-service (DoS) conditions by downloading a crafted RAR compressed file onto a LAN-side host if the firewall has the “Anti-Malware” feature enabled.

cvss

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

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.15.3mediumCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 1.6 · impact 3.6

v3.16.5mediumAV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.16.5mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.16.5mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · security@zyxel.com.twexploitability 2.8 · impact 3.6

v3.14.9mediumCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-476USCWE-476US

affected products (42)

Products and version ranges known to be affected.

Zyxel ATP series firmware≤ version 4.32 through 5.37 Patch 1enisa_euvdEU
Zyxel USG FLEX series firmware≤ version 4.50 through 5.37 Patch 1enisa_euvdEU
Zyxel Communications Corp. ATP4.32 → 5.37 Patch 1fstec_bduRU
Zyxel Communications Corp. USG FLEX4.50 → 5.37 Patch 1fstec_bduRU
zyxel atp100 firmware4.32 → 5.37nvdUScpe:2.3:o:zyxel:atp100_firmware:*:*:*:*:*:*:*:*
zyxel atp100 firmware= 5.37nvdUScpe:2.3:o:zyxel:atp100_firmware:*:*:*:*:*:*:*:*
zyxel atp100w firmware4.32 → 5.37nvdUScpe:2.3:o:zyxel:atp100w_firmware:*:*:*:*:*:*:*:*
zyxel atp100w firmware= 5.37nvdUScpe:2.3:o:zyxel:atp100w_firmware:*:*:*:*:*:*:*:*
zyxel atp200 firmware4.32 → 5.37nvdUScpe:2.3:o:zyxel:atp200_firmware:*:*:*:*:*:*:*:*
zyxel atp200 firmware= 5.37nvdUScpe:2.3:o:zyxel:atp200_firmware:*:*:*:*:*:*:*:*
zyxel atp500 firmware4.32 → 5.37nvdUScpe:2.3:o:zyxel:atp500_firmware:*:*:*:*:*:*:*:*
zyxel atp500 firmware= 5.37nvdUScpe:2.3:o:zyxel:atp500_firmware:*:*:*:*:*:*:*:*
zyxel atp700 firmware4.32 → 5.37nvdUScpe:2.3:o:zyxel:atp700_firmware:*:*:*:*:*:*:*:*
zyxel atp700 firmware= 5.37nvdUScpe:2.3:o:zyxel:atp700_firmware:*:*:*:*:*:*:*:*
zyxel atp800 firmware4.32 → 5.37nvdUScpe:2.3:o:zyxel:atp800_firmware:*:*:*:*:*:*:*:*
zyxel atp800 firmware= 5.37nvdUScpe:2.3:o:zyxel:atp800_firmware:*:*:*:*:*:*:*:*
zyxel usg flex 100 firmware4.50 → 5.37nvdUScpe:2.3:o:zyxel:usg_flex_100_firmware:*:*:*:*:*:*:*:*
zyxel usg flex 100 firmware= 5.37nvdUScpe:2.3:o:zyxel:usg_flex_100_firmware:*:*:*:*:*:*:*:*
zyxel usg flex 100ax firmware4.50 → 5.37nvdUScpe:2.3:o:zyxel:usg_flex_100ax_firmware:*:*:*:*:*:*:*:*
zyxel usg flex 100ax firmware= 5.37nvdUScpe:2.3:o:zyxel:usg_flex_100ax_firmware:*:*:*:*:*:*:*:*

showing 20 of 42

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2024-0421Zyxel Firewall: Mehrere SchwachstellenDeutsch2024-02-19csaf · cert_bundDE
Ein entfernter Angreifer kann mehrere Schwachstellen in Zyxel Firewall ausnutzen, um einen Denial-of-Service-Zustand zu erzeugen oder beliebigen Code auszuführen.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd cert_bund NVD CVE.org MITRE

published 2024-02-20modified 2026-06-17

references (4)

External citations — patches, advisories, analysis.

scry

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