CVE-2023-28767

highpriority · track · 0EPSS 0.004 · 34 %ileDEEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.40% (34th) EPSS

CVSS 8.8 · high

Is it mine?

32 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

The configuration parser fails to sanitize user-controlled input in the Zyxel ATP series firmware versions 5.10 through 5.36, USG FLEX series firmware versions 5.00 through 5.36, USG FLEX 50(W) series firmware versions 5.10 through 5.36, USG20(W)-VPN series firmware versions 5.10 through 5.36, and VPN series firmware versions 5.00 through 5.36. An unauthenticated, LAN-based attacker could leverage the vulnerability to inject some operating system (OS) commands into the device configuration data on an affected device when the cloud management mode is enabled.

cvss

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

8.8

010

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

v3.18.8highAV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.18.8highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.18.8highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · security@zyxel.com.twexploitability 2.8 · impact 5.9

v3.18.1highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

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

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-78USprimaryCWE-78US

affected products (32)

Products and version ranges known to be affected.

Zyxel ATP series firmware≤ 5.10 through 5.36enisa_euvdEU
Zyxel USG FLEX 50(W) series firmware≤ 5.10 through 5.36enisa_euvdEU
Zyxel USG FLEX series firmware≤ 5.00 through 5.36enisa_euvdEU
Zyxel USG20(W)-VPN series firmware≤ 5.10 through 5.36enisa_euvdEU
Zyxel VPN series Firmware≤ 5.00 through 5.36enisa_euvdEU
Zyxel Communications Corp. ATP5.10 → 5.36fstec_bduRU
Zyxel Communications Corp. USG FLEX5.00 → 5.36fstec_bduRU
Zyxel Communications Corp. USG FLEX 50(W)5.10 → 5.36fstec_bduRU
Zyxel Communications Corp. USG USG20(W)-VPN5.10 → 5.36fstec_bduRU
Zyxel Communications Corp. VPN5.00 → 5.36fstec_bduRU
zyxel usg 20w-vpn firmware5.10 → 5.37nvdUScpe:2.3:o:zyxel:usg_20w-vpn_firmware:*:*:*:*:*:*:*:*
zyxel usg 2200-vpn firmware5.00 → 5.37nvdUScpe:2.3:o:zyxel:usg_2200-vpn_firmware:*:*:*:*:*:*:*:*
zyxel usg flex 100 firmware5.00 → 5.37nvdUScpe:2.3:o:zyxel:usg_flex_100_firmware:*:*:*:*:*:*:*:*
zyxel usg flex 100w firmware5.00 → 5.37nvdUScpe:2.3:o:zyxel:usg_flex_100w_firmware:*:*:*:*:*:*:*:*
zyxel usg flex 200 firmware5.00 → 5.37nvdUScpe:2.3:o:zyxel:usg_flex_200_firmware:*:*:*:*:*:*:*:*
zyxel usg flex 50 firmware5.00 → 5.37nvdUScpe:2.3:o:zyxel:usg_flex_50_firmware:*:*:*:*:*:*:*:*
zyxel usg flex 500 firmware5.00 → 5.37nvdUScpe:2.3:o:zyxel:usg_flex_500_firmware:*:*:*:*:*:*:*:*
zyxel usg flex 50w firmware5.00 → 5.37nvdUScpe:2.3:o:zyxel:usg_flex_50w_firmware:*:*:*:*:*:*:*:*
zyxel usg flex 700 firmware5.00 → 5.37nvdUScpe:2.3:o:zyxel:usg_flex_700_firmware:*:*:*:*:*:*:*:*
zyxel zywall atp100 firmware5.10 → 5.37nvdUScpe:2.3:o:zyxel:zywall_atp100_firmware:*:*:*:*:*:*:*:*

showing 20 of 32

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-1765Zyxel Firewall: Mehrere SchwachstellenDeutsch2023-07-17csaf · cert_bundDE
Ein Angreifer aus dem angrenzenden Netz kann mehrere Schwachstellen in Zyxel Firewall ausnutzen, um beliebigen Programmcode auszuführen oder einen Denial of Service Zustand herbeizuführen.

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 2023-07-17modified 2026-06-17

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references (4)

External citations — patches, advisories, analysis.

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