CVE-2023-28771

criticalpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.993 · 100 %ileexploit · weaponizedDEEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV · 4 exploits · weaponized

Likely / severe?

99.3% (100th) EPSS

CVSS 9.8 · critical

Is it mine?

44 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

added 2023-05-31remediate by 2023-06-21

required action Apply updates per vendor instructions.

EPSS · scored 2026-10-27

Zyxel Multiple Firewalls OS Command Injection Vulnerability

Improper error message handling in Zyxel ZyWALL/USG series firmware versions 4.60 through 4.73, VPN series firmware versions 4.60 through 5.35, USG FLEX series firmware versions 4.60 through 5.35, and ATP series firmware versions 4.60 through 5.35, which could allow an unauthenticated attacker to execute some OS commands remotely by sending crafted packets to an affected 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:Hsecondary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19.8criticalAV:N/AC:L/PR:N/UI:N/S:U/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

ssvc

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

Exploitation: active · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-78USprimaryCWE-78US

exploits (4)

Public proof-of-concept and weaponised exploit code.

exploit/linux/misc/zyxel_ike_decoder_rce_cve_2023_28771Zyxel IKE Packet Decoder Unauthenticated Remote Code Executionweaponized · metasploit
JinParkmida/cve-2023-28771-demoJinParkmida/cve-2023-28771-demoPoC · poc_in_github
benjaminhays/CVE-2023-28771-PoCPoC for CVE-2023-28771 based on Rapid7's excellent writeupPoC · poc_in_github
piecar21/CVE-2023-28771PoC / exploit archive for CVE-2023-28771PoC · poc_in_github

affected products (44)

Products and version ranges known to be affected.

Zyxel ATP series firmware≤ 4.60 through 5.35enisa_euvdEU
Zyxel USG FLEX series firmware≤ 4.60 through 5.35enisa_euvdEU
Zyxel VPN series Firmware≤ 4.60 through 5.35enisa_euvdEU
Zyxel ZyWALL/USG series firmware≤ 4.60 through 4.73enisa_euvdEU
Zyxel Communications Corp. ATP1004.60 → 5.36fstec_bduRU
Zyxel Communications Corp. ATP100W4.60 → 5.35fstec_bduRU
Zyxel Communications Corp. ATP2004.60 → 5.36fstec_bduRU
Zyxel Communications Corp. ATP5004.60 → 5.36fstec_bduRU
Zyxel Communications Corp. ATP7004.60 → 5.36fstec_bduRU
Zyxel Communications Corp. ATP8004.60 → 5.36fstec_bduRU
Zyxel Communications Corp. USG 1104.60 → 4.73fstec_bduRU
Zyxel Communications Corp. USG 3104.60 → 4.73fstec_bduRU
Zyxel Communications Corp. USG FLEX 1004.60 → 5.36fstec_bduRU
Zyxel Communications Corp. USG FLEX 100W4.60 → 5.36fstec_bduRU
Zyxel Communications Corp. USG FLEX 2004.60 → 5.36fstec_bduRU
Zyxel Communications Corp. USG FLEX 504.60 → 5.36fstec_bduRU
Zyxel Communications Corp. USG FLEX 50(W)4.60 → 5.36fstec_bduRU
Zyxel Communications Corp. USG FLEX 5004.60 → 5.36fstec_bduRU
Zyxel Communications Corp. USG FLEX 7004.60 → 5.36fstec_bduRU
Zyxel Communications Corp. VPN1004.60 → 5.36fstec_bduRU

showing 20 of 44

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-1070Zyxel Firewalls: Mehrere SchwachstellenDeutsch2023-04-24csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Zyxel Firewall ausnutzen, um beliebigen Programmcode auszuführen, Informationen offenzulegen, einen Denial of Service zu verursachen, einen Cross Site Scripting Angriff durchzuführen oder die Konfiguration zu manipulieren.

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 CVE.org MITRE

published 2023-04-25modified 2026-06-17

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references (9)

External citations — patches, advisories, analysis.

scry

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