CVE-2026-10221: NousResearch hermes-agent run_agent.py _compress_context injection
A vulnerability was identified in NousResearch hermes-agent up to 0.12.0. Affected by this vulnerability is the function compresscontext of the file runagent.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.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Remove
Remove
NousResearch hermes-agentfrom your environment.Uninstall the NousResearch hermes-agent from affected hosts if the component is not required, or remove the agent until the vendor provides a security fix.
- Configuration
Stop and disable the hermes-agent process/service on all hosts until a vendor patch is available.
NousResearch hermes-agent service_enabled = false - Compensating control
Block or restrict remote access to hosts running the hermes-agent at the network perimeter (firewall/ACLs) and isolate those hosts to trusted networks, since the vulnerability can be exploited remotely.
- Operational
Perform incident response on hosts that ran the hermes-agent: review logs for signs of exploitation (public exploit exists), scan for malicious artifacts, remediate or restore from known-good backups, and follow organization IR procedures. Rotate any credentials or secrets if compromise is suspected.
Event History
Frequently Asked Questions
What is the severity of CVE-2026-10221?
CVE-2026-10221 has a severity rating of 7.3, categorized as high.
How do I fix CVE-2026-10221?
You can mitigate CVE-2026-10221 by upgrading the NousResearch hermes-agent to version 0.12.1 or later.
What type of injection is associated with CVE-2026-10221?
CVE-2026-10221 involves a context injection vulnerability in the function _compress_context of run_agent.py.
Is CVE-2026-10221 exploitable remotely?
Yes, CVE-2026-10221 can be exploited remotely, making it more critical to address.
Are there known exploits for CVE-2026-10221?
Yes, exploits for CVE-2026-10221 are publicly available, increasing the urgency to patch.