Medium · CVSS 4.3CVE-2026-111061GHSA-4WC5-F2RC-Q74M

russh agent server converts constraint records into unbounded never-rolled-back tasksCVE-2026-111061

Answer in brief

CVE-2026-111061 records a Medium severity (CVSS 4.3) vulnerability in russh agent server converts constraint records into unbounded never-rolled-back tasks. The current sources do not mark it as known exploited. The current feed maps Eugeny/russh (generic), russh (rust). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 19, 2026Updated Oct 19, 2026Source checked Oct 19, 2026First seen by HOL Oct 19, 2026Material review Oct 19, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 4.3
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 4.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Eugeny/russh (generic), russh (rust). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Eugeny/russhgeneric	<0.64.1	0.64.1
russhrust	<=0.64.0	0.64.1

Recommended response

Check inventory. Check lockfiles and deployed manifests for Eugeny/russh, russh.
Review the reported fix. Update Eugeny/russh to 0.64.1; russh to 0.64.1 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Oct 19, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Oct 19, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Oct 19, 2026

Sources and claim methodology

Upstream source description

russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. Prior to 0.64.1, the agent server spawns a separate long-lived task for every SSH_AGENT_CONSTRAIN_LIFETIME record in a constrained add-key request. The loop accepts repeated lifetime records, clones the key blob into each task, and does not roll back tasks when later constraint parsing fails. An attacker that can speak the agent protocol locally or through agent forwarding can exhaust memory and tasks until the agent process is starved or terminated, denying SSH agent service. This issue is fixed in version 0.64.1.

Quoted source text, attributed separately from HOL analysis.