Medium severity · published Aug 3, 2026
CVE-2026-68930
Russh: Channel-scoped server callbacks can be reached without an open channel
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
Russh is a Rust SSH client & server library. Prior to 0.62.5, russh dispatches channel-scoped Handler callbacks for recipient channel IDs that were never opened or confirmed in russh/src/server/encrypted.rs, server_read_authenticated, and the exec_request callback. Version 0.62.5 fixes the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 31% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RU
russh · Eugeny
< 0.62.5 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-68930
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-68930
github.com
https://github.com/Eugeny/russh/commit/7c5659f8cf6f6f2f9989d12dba0ebf49dc50a171
github.com
https://github.com/Eugeny/russh/releases/tag/v0.62.5
github.com
https://github.com/Eugeny/russh/security/advisories/GHSA-m65r-rprj-r5rg
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