CVE-2026-116774

russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. From 0.60.0 until 0.65.0, channel-open parsing accepts a peer-declared maximum_packet_size of zero and passes it into ChannelTx::poll_writable in russh/src/channels/io/tx.rs. The Channel::data, Channel::make_writer, and Channel::into_stream asynchronous write paths then calculate a writable size of zero and remain pending forever because window adjustments cannot satisfy a static zero packet maximum. An authenticated client can strand server writes, and a malicious server can strand client writes, allowing affected tasks, channels, and connections to accumulate without surfacing an error. 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 LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/Eugeny/russh/commit/39cb9dbaa37caf555d34c6c22efa3bbbff9e186c
https://github.com/Eugeny/russh/releases/tag/v0.65.0
https://github.com/Eugeny/russh/security/advisories/GHSA-fw5c-8223-6h42

Configurations

No configuration.

History

27 Oct 2026, 21:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-27 21:18

Updated : 2026-10-28 17:18

NVD link : CVE-2026-116774

Mitre link : CVE-2026-116774

CVE.ORG link : CVE-2026-116774

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

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