A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36 Patch 1, USG FLEX series firmware versions 4.60 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.60 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.
A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36 Patch 1, USG FLEX series firmware versions 4.60 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.60 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.60 through 5.36 Patch 1, VPN series firmware versions 4.60 through 5.36 Patch 1, ZyWALL/USG series firmware versions…
Apply updates per vendor instructions.
This vulnerability is currently on the CISA KEV list, which CISA only adds CVEs to when there is reliable evidence of active exploitation in the wild. For federal civilian agencies, BOD 22-01 requires remediation by the due date above. For everyone else, KEV is the strongest "patch immediately" signal you can get from public threat intel.
| Vendor | Product | Versions |
|---|---|---|
| Zyxel | ATP series firmware | 4.60 through 5.36 Patch 1 |
| Zyxel | USG FLEX series firmware | 4.60 through 5.36 Patch 1 |
| Zyxel | USG FLEX 50(W) firmware | 4.60 through 5.36 Patch 1 |
| Zyxel | USG20(W) | VPN firmware — 4.60 through 5.36 Patch 1 |
| Zyxel | VPN series firmware | 4.60 through 5.36 Patch 1 |
| Zyxel | ZyWALL/USG series firmware | 4.60 through 4.73 Patch 1 |
Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection: