russh: Agent server never calls `Agent::confirm`, so keys added with the confirm constraint (`ssh-add -c`) sign without confirmation

Summary The agent server in russh::keys::agent::server never calls Agent::confirm before signing with a key that was added with the confirm constraint. That constraint is SSHAGENTCONSTRAINCONFIRM RFC 9987 §5.2.7.2, which is what ssh-add -c sends. The call was replaced by a hard-coded true in...

GHSA-VP5Q-FF62-JWQV russh: Agent server never calls `Agent::confirm`, so keys added with the confirm constraint (`ssh-add -c`) sign without confirmation

Summary The agent server in russh::keys::agent::server never calls Agent::confirm before signing with a key that was added with the confirm constraint. That constraint is SSHAGENTCONSTRAINCONFIRM RFC 9987 §5.2.7.2, which is what ssh-add -c sends. The call was replaced by a hard-coded true in...

EUVD-2026-112267

russh: Agent server never calls Agent::confirm, so keys added with the confirm constraint ssh-add -c sign without confirmation...

GHSA-FW5C-8223-6H42 russh: peer-declared zero maximum packet size permanently stalls channel writes (silent AsyncWrite hang)

Summary A peer can advertise maximum packet size = 0 in its channel-open message CHANNELOPEN when attacking a server, CHANNELOPENCONFIRMATION when attacking a client. russh accepts the value without validation and copies it into the channel write state, where it caps the size of every outgoing da...

EUVD-2026-111389

russh: peer-declared zero maximum packet size permanently stalls channel writes silent AsyncWrite hang...

russh: peer-declared zero maximum packet size permanently stalls channel writes (silent AsyncWrite hang)

Summary A peer can advertise maximum packet size = 0 in its channel-open message CHANNELOPEN when attacking a server, CHANNELOPENCONFIRMATION when attacking a client. russh accepts the value without validation and copies it into the channel write state, where it caps the size of every outgoing da...

russh's SSH agent server is susceptible to unbound allocations via repeated SSH_AGENT_CONSTRAIN_CONFIRM messages

Summary All evidence, reproduction steps, and scripts in the report were verified against a real running instance. Nothing is fabricated or synthetic; every verdict is backed by captured output from an actual deployment. The SSH agent server that ships with russh russh::keys::agent::server::serve...

GHSA-9WFM-JCJ8-JFV9 russh's SSH agent server is susceptible to unbound allocations via repeated SSH_AGENT_CONSTRAIN_CONFIRM messages

Summary All evidence, reproduction steps, and scripts in the report were verified against a real running instance. Nothing is fabricated or synthetic; every verdict is backed by captured output from an actual deployment. The SSH agent server that ships with russh russh::keys::agent::server::serve...

EUVD-2026-111387

russh's SSH agent server is susceptible to unbound allocations via repeated SSHAGENTCONSTRAINCONFIRM messages...

russh's SSH client is susceptible to unbounded allocations via EXT_INFO packets

Summary All evidence, reproduction steps, and scripts in the report were verified against a real running instance. Nothing is fabricated or synthetic; every verdict is backed by captured output from an actual deployment. Concretely, the evidence comes from executing the real russh v0.64.1 client...

GHSA-4P9F-7P9M-5VFG russh's SSH client is susceptible to unbounded allocations via EXT_INFO packets

Summary All evidence, reproduction steps, and scripts in the report were verified against a real running instance. Nothing is fabricated or synthetic; every verdict is backed by captured output from an actual deployment. Concretely, the evidence comes from executing the real russh v0.64.1 client...

EUVD-2026-111388

russh's SSH client is susceptible to unbounded allocations via EXTINFO packets...

CVE-2026-116794

A flaw was found in russh. When processing signing requests for SSH keys configured to require explicit confirmation, the SSH agent server component fails to invoke the confirmation check and automatically returns success. A local process or remote user with access to the forwarded SSH agent sock...

CVE-2026-116774

A flaw was found in russh. An authenticated remote client or a malicious server can cause a denial of service DoS by declaring a maximum packet size of zero during SSH channel negotiation. The affected system accepts this value, causing asynchronous write operations to hang indefinitely and...

CVE-2026-116696

A flaw was found in russh. This vulnerability can lead to a Denial of Service DoS due to unbounded memory consumption in the SSH agent service. A local process or a remote user with access to a forwarded agent socket can repeatedly submit keys containing an excessive number of confirmation...

CVE-2026-116773

A flaw was found in russh. An unbounded memory allocation issue allows a malicious Secure Shell SSH server to cause a Denial of Service DoS on connecting clients. By repeatedly sending crafted pre-authentication extension packets, the server forces the client to store an unlimited number of...

CVE-2026-116794

russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. From 0.50.0-beta.12 until 0.65.0, the agent server's Connection::trysign path in russh/src/keys/agent/server.rs recognizes SSHAGENTCONSTRAINCONFIRM but returns a hard-coded successful result instead ...

Linux Distros Unpatched Vulnerability : CVE-2026-116794

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. From 0.50.0-beta.12 until 0.65.0, the agent server's...

DEBIAN-CVE-2026-116794

russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. From 0.50.0-beta.12 until 0.65.0, the agent server's Connection::trysign path in russh/src/keys/agent/server.rs recognizes SSHAGENTCONSTRAINCONFIRM but returns a hard-coded successful result instead ...

CVE-2026-116794

russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. From 0.50.0-beta.12 until 0.65.0, the agent server's Connection::trysign path in russh/src/keys/agent/server.rs recognizes SSHAGENTCONSTRAINCONFIRM but returns a hard-coded successful result instead ...