VulnTideExploited vulnerabilities, by vendor. Data as of 28 Oct 2026.
Known exploitedIn CISA's KEV catalog since 16 May 2022Ransomware use: unknown
Zyxel Multiple Firewalls

CVE-2022-30525: Zyxel Multiple Firewalls OS Command Injection Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 16 May 2022, 4 days after the CVE record was published.

How likely is exploitation in the next 30 days?
99.9%

EPSS score, percentile 100 of all scored records

How severe?
9.8 Critical

CVSS v3.1 base score, given by the CNA

What should I do?

CISA deadline 6 Jun 2022. Apply updates per vendor instructions.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

  • 5.00 through 5.21 Patch 1
  • 5.00 through 5.21 Patch 1
  • 5.00 through 5.21 Patch 1
  • 5.00 through 5.21 Patch 1
  • 5.10 through 5.21 Patch 1
  • 4.60 through 5.21 Patch 1

and 2 more in the table below

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

Required action, set by CISA

Apply updates per vendor instructions.

CISA due date for this action: 6 June 2022.

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

Linked from CISA's catalog entry

Affected products and versions

As listed in the CVE record.

Zyxel USG FLEX 100(W) firmware
StatusVersions
Affected5.00 through 5.21 Patch 1
Zyxel USG FLEX 200 firmware
StatusVersions
Affected5.00 through 5.21 Patch 1
Zyxel USG FLEX 500 firmware
StatusVersions
Affected5.00 through 5.21 Patch 1
Zyxel USG FLEX 700 firmware
StatusVersions
Affected5.00 through 5.21 Patch 1
Zyxel ATP series firmware
StatusVersions
Affected5.10 through 5.21 Patch 1
Zyxel VPN series firmware
StatusVersions
Affected4.60 through 5.21 Patch 1
Zyxel USG FLEX 50(W) firmware
StatusVersions
Affected5.10 through 5.21 Patch 1
Zyxel USG 20(W)-VPN firmware
StatusVersions
Affected5.10 through 5.21 Patch 1

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

A command injection vulnerability in the CGI program of some Zyxel firewall versions could allow an attacker to modify specific files and then execute some OS commands on a vulnerable device.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

  • CISA added CVE-2022-30525 to its Known Exploited Vulnerabilities (KEV) catalog on 16 May 2022.
  • CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
  • The due date CISA sets for the required action is 6 Jun 2022.
  • The CVE record was published on 12 May 2022, 4 days before it was added to KEV.
  • The CVE record carries a CVSS v3.1 base score of 9.8 (Critical), given by its CNA.
  • FIRST's EPSS model puts the probability of exploitation in the next 30 days at 99.9% (percentile 100), as of 28 Oct 2026.
  • CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

A OS command injection vulnerability in the CGI program of Zyxel USG FLEX 100(W) firmware versions 5.00 through 5.21 Patch 1, USG FLEX 200 firmware versions 5.00 through 5.21 Patch 1, USG FLEX 500 firmware versions 5.00 through 5.21 Patch 1, USG FLEX 700 firmware versions 5.00 through 5.21 Patch 1, USG FLEX 50(W) firmware versions 5.10 through 5.21 Patch 1, USG20(W)-VPN firmware versions 5.10 through 5.21 Patch 1, ATP series firmware versions 5.10 through 5.21 Patch 1, VPN series firmware versions 4.60 through 5.21 Patch 1, which could allow an attacker to modify specific files and then execute some OS commands on a vulnerable device.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

  • CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

DateEvent
12 May 2022CVE record published
16 May 2022Added to CISA KEV
6 Jun 2022CISA due date for the required action
21 Oct 2025CVE record last updated

References

More exploited Zyxel vulnerabilities

  • CVE-2026-7273: Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability (added 21 Sep 2026)
  • CVE-2024-40890: Zyxel DSL CPE OS Command Injection Vulnerability (added 11 Feb 2025)
  • CVE-2024-40891: Zyxel DSL CPE OS Command Injection Vulnerability (added 11 Feb 2025)
  • CVE-2024-11667: Zyxel Multiple Firewalls Path Traversal Vulnerability (added 3 Dec 2024)
  • CVE-2017-6884: Zyxel EMG2926 Routers Command Injection Vulnerability (added 18 Sep 2023)
  • CVE-2017-18368: Zyxel P660HN-T1A Routers Command Injection Vulnerability (added 7 Aug 2023)