CVE-2021-36369
Fixed in a distro release EPSS 2%CVSS 7.5
An issue was discovered in Dropbear through 2020.81. Due to a non-RFC-compliant check of the available authentication methods in the client-side SSH code, it is possible for an SSH server to change the login process in its favor. This attack can bypass additional security measures such as FIDO2 tokens or SSH-Askpass. Thus, it allows an attacker to abuse a forwarded agent for logging on to another server unnoticed.
Products: dropbear_ssh_project dropbear_ssh, debian_linux
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Debian 10 | dropbear | 2018.76-5+deb10u2 |
| Debian 12 | dropbear | 2022.82-1 |
| Debian 13 | dropbear | 2022.82-1 |
| Debian 14 | dropbear | 2022.82-1 |
| Ubuntu 16.04 LTS | dropbear | no fix |
| Ubuntu 22.04 LTS | dropbear | 2020.81-5ubuntu0.1 |
| Ubuntu Pro 18.04 LTS | dropbear | 2017.75-3ubuntu0.1~esm1 |
| Ubuntu Pro 20.04 LTS | dropbear | 2019.78-2ubuntu0.1~esm1 |