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InjectionWeakness · CWE-74

CVE-2026-10221

HIGH · 7.3 CVSS v3.1 Published 2026-06-01
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
82/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A vulnerability was identified in NousResearch hermes-agent up to 0.12.0. Affected by this vulnerability is the function _compress_context of the file run_agent.py. The manipulation leads to injection. It is possible to initiate the attack remotely. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

A code injection vulnerability exists in the _compress_context function of NousResearch hermes-agent (versions up to 0.12.0). The vulnerability allows remote attackers to inject malicious input through context compression, likely enabling prompt injection attacks against the AI agent. The exploit is publicly available, increasing risk.

MitigationImplement strict input validation and sanitization on all data flowing into _compress_context before it reaches the LLM. Consider context isolation or sandboxing to prevent injection through compressed context.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
Low

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check installed hermes-agent version
    Run 'pip show hermes-agent' or check the package version in your environment
    Affected if version is 0.12.0 or lower (any version up to and including 0.12.0)
  2. Locate run_agent.py in the hermes-agent installation
    Find the run_agent.py file within the hermes-agent package directory
    Affected if the file exists and contains the _compress_context function
  3. Inspect the _compress_context function
    Open run_agent.py and locate the _compress_context function definition
    Affected if the function processes context data without visible input sanitization or validation
  4. Determine if context compression is enabled or used
    Check the code flow to see if _compress_context is called during agent execution, or check configuration for context processing settings
    Affected if the function is actively used in the agent workflow

You are affected if hermes-agent version is 0.12.0 or lower and the _compress_context function in run_agent.py is present and used in your environment.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Implement strict input validation and sanitization on all data flowing into _compress_context before it reaches the LLM. Consider context isolation or sandboxing to prevent injection through compressed context.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-10221 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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