A downgrade from two-factor authentication to one-factor authentication vulnerability in the CGI program of Zyxel USG/ZyWALL series firmware versions 4.32 through 4.71, USG FLEX series firmware versions 4.50 through 5.21, ATP series firmware versions 4.32 through 5.21, and VPN series firmware versions 4.32 through 5.21, that could allow an authenticated attacker to bypass the second authentication phase to connect the IPsec VPN server even though the two-factor authentication (2FA) was enabled.
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No Fix Known
No patch has been released yet. Apply workarounds or mitigations where available.
| Vendor | Product | Versions | Fixed In |
|---|---|---|---|
| zyxel | vpn100_firmware | 4.32 - 5.21 | - |
| zyxel | vpn1000_firmware | 4.32 - 5.21 | - |
| zyxel | vpn300_firmware | 4.32 - 5.21 |
Published
CVE disclosed publicly
Last Modified
Most recent update
Indexed to CVEInsight
Added to this platform
AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
32
Affected Products
2
References
zyxel / vpn100_firmware
| - |
| zyxel | vpn50_firmware | 4.32 - 5.21 | - |
| zyxel | atp100_firmware | 4.32 - 5.21 | - |
| zyxel | atp100w_firmware | 4.32 - 5.21 | - |
| zyxel | atp200_firmware | 4.32 - 5.21 | - |
| zyxel | atp500_firmware | 4.32 - 5.21 | - |
| zyxel | atp700_firmware | 4.32 - 5.21 | - |
| zyxel | atp800_firmware | 4.32 - 5.21 | - |
| zyxel | usg_110_firmware | 4.32 - 4.71 | - |
| zyxel | usg_1100_firmware | 4.32 - 4.71 | - |
| zyxel | usg_1900_firmware | 4.32 - 4.71 | - |
| zyxel | usg_20w_firmware | 4.32 - 4.71 | - |
| zyxel | usg_20w-vpn_firmware | 4.32 - 4.71 | - |
| zyxel | usg_2200-vpn_firmware | 4.32 - 4.71 | - |
| zyxel | usg_310_firmware | 4.32 - 4.71 | - |
| zyxel | usg_40_firmware | 4.32 - 4.71 | - |
| zyxel | usg_40w_firmware | 4.32 - 4.71 | - |
| zyxel | usg_60_firmware | 4.32 - 4.71 | - |
| zyxel | usg_60w_firmware | 4.32 - 4.71 | - |
| zyxel | usg_flex_100_firmware | 4.50 - 5.21 | - |
| zyxel | usg_flex_100w_firmware | 4.50 - 5.21 | - |
| zyxel | usg_flex_200_firmware | 4.50 - 5.21 | - |
| zyxel | usg_flex_500_firmware | 4.50 - 5.21 | - |
| zyxel | usg_flex_700_firmware | 4.50 - 5.21 | - |
| zyxel | usg200_firmware | 4.32 - 4.71 | - |
| zyxel | usg20_firmware | 4.32 - 4.71 | - |
| zyxel | usg210_firmware | 4.32 - 4.71 | - |
| zyxel | usg2200_firmware | 4.32 - 4.71 | - |
| zyxel | usg300_firmware | 4.32 - 4.71 | - |
| zyxel | usg310_firmware | 4.32 - 4.71 | - |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Exploitability
Impact