Background exploitation KEV catalog No authentication

CVE-2022-30525

Zyxel Multiple Firewalls OS Command Injection Vulnerability

CheckOps priority index

9.3/10 Patch within 24 h

Severity9.8

Probability10.0

Exploitation4/5

Severity = CVSS. Probability = EPSS (FIRST). Exploitation = public signals: KEV, EUVD, ransomware, EPSS above 10 %, no account required.

EPSS · today 99.9% higher than 99.97% of CVEs

CVSS 3.1 9.8 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:

Exploited for 1,632 days 16 May 2022

CISA due date 06 Jun 2022 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 4 / 5

KEV catalog (CISA)16 May 2022
Exploited in EUVD (ENISA)16 May 2022
Used by ransomwareno
EPSS above 10 %99.9%
No account, over the networkyes

What to do

Fix

Apply the vendor’s fix as soon as it is available.

CISA guidance: Apply updates per vendor instructions.

Meanwhile

Take the service off the internet or restrict access to it, watch the logs and look for signs of compromise.

Manufacturers (CRA)

Exploited vulnerability in your product: early warning to ENISA within 24 h, then notification within 72 h (Article 14 of the Cyber Resilience Act). The CRA explained

Description ENISA EUVD

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.

Affected products

USG FLEX 100(W) firmwareUSG FLEX 200 firmwareUSG FLEX 50(W) firmwareUSG FLEX 700 firmwareATP series firmwareVPN series FirmwareUSG 20(W)-VPN firmwareUSG FLEX 500 firmwareMultiple Firewalls

Affected versions

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

Weaknesses (CWE)

CWE-78

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

12 May 2022
Published
16 May 2022
Exploitation reported (ENISA)
16 May 2022
Added to the KEV catalog
06 Jun 2022
CISA remediation due date
26 Sept 2026
EPSS peak: 99.9%

References

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CVE-2017-6884Zyxel EMG2926 Routers Command Injection Vulnerability
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