Description
Use-after-free vulnerability in Dropbear SSH Server 0.52 through 2012.54, when command restriction and public key authentication are enabled, allows remote authenticated users to execute arbitrary code and bypass command restrictions via multiple crafted command requests, related to "channels concurrency."
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 | 2012.55-1 | — |
| Debian 13 | dropbear | 2012.55-1 | — |
| Debian 12 | dropbear | 2012.55-1 | — |
| Debian 6.0 | dropbear | 0.52-5+squeeze1 | DSA-2456-1 |
Advisories 1
- DSA-2456-1 dropbear - use after free Debian Security (DSA / DLA) · Mar 9, 2026
References
- dropbear-code-execution(73444) vdb-entry
- 48147 third-party-advisory
- DSA-2456 vendor-advisory
- 79590 vdb-entry
- http://matt.ucc.asn.au/dropbear/CHANGES
- 52159 vdb-entry
- https://secure.ucc.asn.au/hg/dropbear/rev/818108bf7749
- https://www.mantor.org/~northox/misc/CVE-2012-0920.html
- 48929 third-party-advisory