CVE-2023-28769

criticalpriority · attend · 51EPSS 0.054 · 93 %ileexploit · functionalDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · functional

Likely / severe?

5.42% (93rd) EPSS

CVSS 9.8 · critical

Is it mine?

4 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

The buffer overflow vulnerability in the library “libclinkc.so” of the web server “zhttpd” in Zyxel DX5401-B0 firmware versions prior to V5.17(ABYO.1)C0 could allow a remote unauthenticated attacker to execute some OS commands or to cause denial-of-service (DoS) conditions on a vulnerable device.

cvss

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

9.8

010

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

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19.6criticalAV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · security@zyxel.com.twexploitability 3.9 · impact 5.9

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

ssvc

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

Exploitation: none · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-120USprimaryCWE-120US

exploits (1)

Public proof-of-concept and weaponised exploit code.

exploit/linux/misc/zyxel_multiple_devices_zhttp_lan_rceZyxel Unauthenticated LAN Remote Code Executionfunctional · metasploit

affected products (4)

Products and version ranges known to be affected.

Zyxel Firewall VPN2Sall versionscert_bundDEcpe:/h:zyxel:firewall:vpn2s
Zyxel DX5401-B0 firmware≤ < V5.17(ABYO.1)C0enisa_euvdEU
Zyxel Communications Corp. DX5401-B0≤ 5.17(ABYO.1)C0fstec_bduRU
zyxel dx5401-b0 firmware< 5.17\(abyo.1\)c0nvdUScpe:2.3:o:zyxel:dx5401-b0_firmware:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-1091Zyxel Firewall Produkte: Mehrere SchwachstellenDeutsch2022-02-15csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Zyxel Firewall Produkten ausnutzen, um beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen, seine Privilegien zu erweitern und einen Cross-Site-Scripting-Angriff durchzuführen.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund nvd NVD CVE.org MITRE

published 2023-04-27modified 2026-06-17

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+5664 more

references (4)

External citations — patches, advisories, analysis.

scry

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