CVE-2026-116773

russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. Prior to 0.65.0, the client Session::process_packet path in russh/src/client/encrypted.rs accepts repeated packets encoded with russh's private msg::EXT_INFO = 7 before authentication, while the standards-compliant EXT_INFO message number 82 does not reach the affected handler. The handle_ext_info function appends every parsed extension name to received_extensions without clearing, deduplicating, or bounding the vector. A malicious SSH server that deliberately sends private message number 7 can therefore retain an unbounded number of attacker-controlled extension names for the session lifetime, causing progressive client memory exhaustion. This issue is fixed in version 0.65.0.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/Eugeny/russh/commit/b33e93beec393e6d29eee69c1b8831736724ee75
https://github.com/Eugeny/russh/releases/tag/v0.65.0
https://github.com/Eugeny/russh/security/advisories/GHSA-4p9f-7p9m-5vfg
https://github.com/Eugeny/russh/security/advisories/GHSA-4p9f-7p9m-5vfg

Configurations

No configuration.

History

30 Oct 2026, 16:17

Type	Values Removed	Values Added
References	~~() https://github.com/Eugeny/russh/security/advisories/GHSA-4p9f-7p9m-5vfg -~~	() https://github.com/Eugeny/russh/security/advisories/GHSA-4p9f-7p9m-5vfg -

27 Oct 2026, 21:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-27 21:18

Updated : 2026-10-30 16:17

NVD link : CVE-2026-116773

Mitre link : CVE-2026-116773

CVE.ORG link : CVE-2026-116773

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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