Description
The server in Dropbear before 2017.75 might allow post-authentication root remote code execution because of a double free in cleanup of TCP listeners when the -a option is enabled.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | dropbear | 2016.74-5 | — |
| Debian 13 | dropbear | 2016.74-5 | — |
| Debian 12 | dropbear | 2016.74-5 | — |
| Debian 8 | dropbear | 2014.65-1+deb8u2 | DSA-3859-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | dropbear | No fix yet | — |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.5 | dropbear | 2017.75-r0 | — |
| Alpine v3.4 | dropbear | 2017.75-r0 | — |
Advisories 1
- DSA-3859-1 dropbear - security update Debian Security (DSA / DLA) · Mar 9, 2026