CVE-2026-48108 json
Russh: SSH identification parsing accepted non-canonical client banners and did not bound pre-banner input
published 2026-06-10 4 mo ago modified 2026-07-23 3 mo ago also EUVD-2026-36130 , GHSA-76r6-x97p-67vr
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 20%
- public exploits
- 0
- none known
Summary
Russh is a Rust SSH client & server library. From version 0.34.0-beta.1 to before version 0.61.0, russh did not enforce the SSH identification-string rules as deliberately as OpenSSH. In particular, the server-side identification reader used the same permissive path as the client, allowing pre-banner lines from clients, and the reader did not enforce a bounded number of pre-banner lines. For a library server built on russh, this could allow a remote peer to hold connection setup resources in the cleartext pre-authentication phase with malformed identification input that should have been rejected early. This issue has been patched in version 0.61.0.
Patch / fix
- crates.io russh 0.61.0
- russh_project russh 0.61.0
- warpgate_project warpgate 0.61.0
- rust-russh Debian 14 0.64.1-1
debian advisories DEBIAN-CVE-2026-48108
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 4 mo ago
Exploit prediction
0.28% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/Eugeny/russh/security/advisories/GHSA-76r6-x97p-67vr referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| GitHub | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| crates.io | russh | >=0.34.0-beta.1, <0.61.0 |
0.61.0 |
Affected products
- Eugeny russh
Classification
- Weakness
-
- CWE-20 Improper Input Validation
References
-
github.com
/Eugeny/russh/security/advisories/GHSA-76r6-x97p-67vr
exploit, web
-
nvd.nist.gov
/vuln/detail/CVE-2026-48108
advisory
-
github.com
/Eugeny/russh
package
Sources
- CVE List CVE-2026-48108
- GitHub Advisory GHSA-76r6-x97p-67vr
- NVD CVE-2026-48108
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.