CVE-2023-28771
CriticalActively exploited (CISA KEV)
Description
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.
SeverityCritical
CVSS9.8
Exploit probability—
Product
Zyxel Multiple Firewalls
PublishedApr 25, 2023
First seenApr 25, 2023
Added to KEVMay 31, 2023
Weakness typeCWE-78OS command injection
How to fix
CISA required action
Apply updates per vendor instructions.
CISA due date: Jun 21, 2023Update
- zyxel zywall_usg_310_firmware4.73 or later
- zyxel atp100_firmware5.36 or later
- zyxel atp100w_firmware5.35 or later
- zyxel atp200_firmware5.36 or later
- zyxel atp500_firmware5.36 or later
- zyxel atp700_firmware5.36 or later
- zyxel atp800_firmware5.36 or later
- zyxel usg_flex_100_firmware5.36 or later
- zyxel usg_flex_100w_firmware5.36 or later
- zyxel usg_flex_200_firmware5.36 or later
- zyxel usg_flex_50_firmware5.36 or later
- zyxel usg_flex_500_firmware5.36 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| zyxel zywall_usg_310_firmware | 4.60 ≤ v < 4.73, 4.73 | 4.73 |
| zyxel atp100_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel atp100w_firmware | 4.60 ≤ v < 5.35 | 5.35 |
| zyxel atp200_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel atp500_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel atp700_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel atp800_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel usg_flex_100_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel usg_flex_100w_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel usg_flex_200_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel usg_flex_50_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel usg_flex_500_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel usg_flex_50w_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel usg_flex_700_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel vpn100_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel vpn1000_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel vpn300_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel vpn50_firmware | 4.60 ≤ v < 5.36 | 5.36 |
| zyxel zywall_usg_100_firmware | 4.60 ≤ v < 4.73, 4.73 | 4.73 |
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