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.
CVE-2026-111061
MEDIUMPre-NVD 4.34.3Trending — 3 sources updated this weekElevatedEG-KEV Tier 3: ElevatedEG-KEV is EchelonGraph's own tiering of exploitation signals from CISA KEV, CISA's SSVC data (Vulnrichment), ransomware data, public exploit-code references and EPSS.Tier 3 is not evidence of exploitation. It means public exploit code is referenced, or CISA's SSVC data says "public PoC", or EPSS ranks the CVE in the top 5%.Signals for this CVE: CISA's SSVC exploitation value: public PoC.EchelonGraph confidence 38%: a heuristic from the tier and the number of signals, not a measured probability.
EchelonGraph scoreLOW confidence
This medium-severity CVE scores 4.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3% (26th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.
Triggered by: Headline CVSS from a secondary CVSS source
Sources: a secondary CVSS source
4.3EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
- CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 4.3Exploit: No code on recordExposed services: Not assessed
A fix is available — apply it.
- CVSS v3
- 4.3
- EG Score
- 4.3MEDIUMlow confidence
- EG Risk
- 35EG Risk 35/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity43% × 45%Impact severity (EG Severity): CVSS 4.3 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation40% × 40%EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.Automatability0% × 15%CISA's SSVC Automatable value: no (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is available. Apply it within your standard update timelines. - EPSS PROB
- 0.3%
- EPSS %ILE
- 26th
- KEV
- Not listed
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (4.3): severity, escalated by confirmed exploitation. This CVE's 4.3 is its impact severity (EG Severity), not escalated.
- EG Severity
- 4.3 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
- EG Likelihood
- 0.3% within 30 daysSource: FIRST EPSS. FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
October 19, 2026
Last Modified
October 19, 2026
Advisory Details (3)
Auto-updated Oct 19, 2026🔬 Proof of concept available. Patch available. Sources: github_commit, github_release, github.
GitHub release Patch Available
v0.64.1
Patch available: Eugeny/russh v0.64.1
https://github.com/Eugeny/russh/releases/tag/v0.64.1GitHub commit Patch Available
commit 4c305033d72f (Eugeny/russh)
Patch available: Eugeny/russh v0.64.1 (contains commit 4c305033d72f)
https://github.com/Eugeny/russh/commit/4c305033d72f8e5dd21a3fd4c53a6c291a16ebd1GitHub advisoryMentions a patch (unverified)🟡 PoC Available
Unbounded memory allocation in agent protocol server via crafted constraint records · Advisory · Eugeny/russh · GitHub
https://github.com/Eugeny/russh/security/advisories/GHSA-4wc5-f2rc-q74mVendor Advisories for CVE-2026-111061(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
crates.io(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| russh | — |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 7× in last 7d / 7× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
- 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.3% · 26th percentile
- 2026-10-20 16:32 UTCEPSS rescoreEPSS 0.3% · 26th percentile
- 2026-10-19 19:30 UTCEG score recompute
- 2026-10-19 18:51 UTCEG score recompute
- 2026-10-19 17:35 UTCEG score recompute
- 2026-10-19 16:48 UTCEG score recomputeFirst assessed: 4.3 MEDIUM
- 2026-10-19 16:47 UTCMITRE cvelistV5first tracked
Related CVEs(same product + same CWE)
Same product
10 showncrates.io:russh
Frequently asked(5)
What is CVE-2026-111061?
CVE-2026-111061 is a medium-severity vulnerability; its CVE record was published on October 19, 2026. 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 SSHAGENTCONSTRAIN_LIFETIME record in a constrained add-key request. The loop accepts repeated lifetime records, clones the…
When was the CVE record for CVE-2026-111061 published?
The CVE record for CVE-2026-111061 was published on October 19, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 19, 2026; the record at its source may have been updated since.
Is CVE-2026-111061 actively exploited?
CVE-2026-111061 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (26th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-111061?
CVE-2026-111061 has a CVSS base score of 4.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-111061?
A fix for CVE-2026-111061 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-111061 are linked in the Vendor Advisories panel on this page.
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-111061
Is Your Infrastructure Affected by CVE-2026-111061?
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