CVE-2026-10222 is a medium-severity (CVSS 5.6) CWE-74 vulnerability in hermes-agent. A fix is available for hermes-agent — see the affected versions and patch details below.
hermes-agent has an Injection issue
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-10222.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-10222 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 388,997 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
hermes-agentReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
A security flaw has been discovered in NousResearch hermes-agent up to 2026.4.30. Affected by this issue is the function _sanitize_env_lines of the file hermes_cli/config.py. The manipulation results in injection. It is possible to launch the attack remotely. The attack requires a high level of complexity. The exploitation is known to be difficult. The exploit has been released to the public and may be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | hermes-agent | all versions | 0.18.0pip install --upgrade 'hermes-agent==0.18.0' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for hermes-agent, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update hermes-agent to 0.18.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-10222 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2026-10222 in your dependencies?
Find it across PyPI, including transitive dependencies.