Vulnerability · Published Oct 12, 2022 · Assigned by mitre
CVE-2021-36369
High 7.5
In plain English
A high-severity improper authentication in the dropbear package (Debian). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.9% (higher than 79% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | dropbear | 2022.82-1 | DEBIAN-CVE-2021-36369 |
| Debian:13 | dropbear | 2022.82-1 | DEBIAN-CVE-2021-36369 |
| Debian:14 | dropbear | 2022.82-1 | DEBIAN-CVE-2021-36369 |
| Ubuntu:22.04:LTS | dropbear | 2020.81-5ubuntu0.1 | USN-7292-1 |
| Ubuntu:22.04:LTS | dropbear | 2020.81-5ubuntu0.1 | UBUNTU-CVE-2021-36369 |
Affected products (as reported)
Weakness: CWE-287 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N