2.2
LOW CVSS 3.1
CVE-2026-128088
russh try_sign: asynchronous confirmation can sign after agent lock
Description

russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. Prior to version 0.65.1, try_sign() captures an Arc<PrivateKey> before awaiting Agent::confirm() and does not revalidate the shared lock state or key presence after the await. This is a distinct residual defect in the remediation for CVE-2026-116794. A peer, including a remote SSH server using agent forwarding, can begin a confirmation-constrained signature request while the agent is unlocked and receive the signature after another connection locks the agent if the stale confirmation returns true. New post-lock requests are rejected and private key material is not disclosed, but the pending operation bypasses the current lock state. This issue is fixed in version 0.65.1.

INFO

Published Date :

Nov. 13, 2026, 7:19 p.m.

Last Modified :

Nov. 13, 2026, 7:19 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-128088 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 LOW [email protected]
Solution
Update russh to version 0.65.1 or later to fix a race condition in the agent protocol implementation.
  • Update russh to version 0.65.1 or later.
  • Ensure agent locks are revalidated after asynchronous operations.
  • Review confirmation logic for agent signature requests.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-128088.

URL Resource
https://github.com/Eugeny/russh/commit/43a46d67a80a7355fcd2fb25e7e00d79aec8184c
https://github.com/Eugeny/russh/pull/808
https://github.com/Eugeny/russh/releases/tag/v0.65.1
https://github.com/Eugeny/russh/security/advisories/GHSA-736f-c93q-9fwx
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-128088 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-128088 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-128088 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-128088 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Nov. 13, 2026

    Action Type Old Value New Value
    Added Description russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. Prior to version 0.65.1, try_sign() captures an Arc<PrivateKey> before awaiting Agent::confirm() and does not revalidate the shared lock state or key presence after the await. This is a distinct residual defect in the remediation for CVE-2026-116794. A peer, including a remote SSH server using agent forwarding, can begin a confirmation-constrained signature request while the agent is unlocked and receive the signature after another connection locks the agent if the stale confirmation returns true. New post-lock requests are rejected and private key material is not disclosed, but the pending operation bypasses the current lock state. This issue is fixed in version 0.65.1.
    Added CVSS V3.1 AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:L/A:N
    Added CWE CWE-367
    Added CWE CWE-863
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/128xxx/CVE-2026-128088.json">CVE-2026-128088</a>
    Added Reference https://github.com/Eugeny/russh/commit/43a46d67a80a7355fcd2fb25e7e00d79aec8184c
    Added Reference https://github.com/Eugeny/russh/pull/808
    Added Reference https://github.com/Eugeny/russh/releases/tag/v0.65.1
    Added Reference https://github.com/Eugeny/russh/security/advisories/GHSA-736f-c93q-9fwx
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.