CVE-2022-30525
CRITICALA 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…
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
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.
Affected Products
atp100 firmwarezyxelatp100w firmwarezyxelatp200 firmwarezyxelatp500 firmwarezyxelatp700 firmwarezyxelatp800 firmwarezyxelResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Zyxel USG FLEX 5.21 - OS Command Injection
by Valentin Lobstein · Jun 3, 2022
Detection & mitigation playbook
Vendor / applianceDetect
Inventory every zyxel atp100 firmware deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for remote code execution at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Fix
Apply the zyxel atp100 firmware security patch or hotfix for CVE-2022-30525 on the affected version, following the vendor advisory for your exact build.
Workarounds
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2022-30525 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.
Tailored to CVE-2022-30525. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2022-30525 being exploited in your environment?
O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2022-30525 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.