# CVE-2026-53870: NousResearch Hermes Agent sensitive information disclosure via world-readable files

Source: https://junglewise.ai/threats/cve-2026-53870-nousresearch-hermes-agent-sensitive-information-disclosure-via  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-17. Updated: 2026-06-20  
License: CC BY 4.0 with a link back

CVE-2026-53870 · Severity: medium · CVSS 5.5 · Published 2026-06-17

Hermes Agent, an AI agent platform, was found to create sensitive data files with overly permissive access settings. This allowed any user with local access to the system to read private conversation histories, AI prompts, and security keys used for webhooks. An attacker could use this information to spy on private interactions or forge authenticated requests to connected services.

Technologies: [NousResearch Hermes Agent](https://junglewise.ai/threats/technologies/hermes-agent), [hermes-agent (PyPI)](https://junglewise.ai/threats/technologies/pypi-hermes-agent). Vendors: [NousResearch](https://junglewise.ai/threats/vendors/nousresearch), [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-53870 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-53870 being exploited in the wild.

**How severe is CVE-2026-53870?** Medium severity, with a CVSS score of 5.5, published 17 June 2026.

**Which products and versions are affected?** NousResearch Hermes Agent < 0.16.0; hermes-agent (PyPI) ECOSYSTEM:introduced=0,fixed=0.16.0.

**Is there a fix for CVE-2026-53870?** Yes. hermes-agent (PyPI): upgrade to 0.16.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-53870 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-53870?** Check whether you run NousResearch Hermes Agent or hermes-agent (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- hermes-agent (PyPI): upgrade to 0.16.0 or later

  ```sh
  pip install "hermes-agent>=0.16.0"
  ```


## Technical details

Hermes Agent versions prior to 0.16.0 suffer from an incorrect default permissions vulnerability (CWE-276). The application created 'response_store.db' (an SQLite database containing conversation history, tool payloads, and prompts) and 'webhook_subscriptions.json' (containing per-route HMAC secrets) using a mode of 0o644. This occurred because the files inherited the process umask (typically 022) rather than being explicitly restricted. A local attacker with filesystem access can read these files to extract sensitive session data or obtain secrets to forge authenticated webhook requests. The issue was resolved in version 0.16.0 by enforcing 0o600 (owner-only) permissions during file creation and narrowing permissions on existing files during subsequent writes.

## Affected products

- NousResearch hermes-agent < 0.16.0

## Identifiers

- CVE-2026-53870
- GHSA-99f9-j8r3-p853
- PYSEC-2026-2511

## Timeline

- 2026-05-23: disclosed: Initial security PR submitted by contributor
- 2026-05-24: patched: Fix merged into main branch
- 2026-06-05: advisory: Version 0.16.0 released with the fix
- 2026-06-17: advisory: CVE-2026-53870 published

## References

- [https://github.com/NousResearch/hermes-agent/commit/3bace071bfadf2d2bec2ee048471a31ec920e3e8](https://github.com/NousResearch/hermes-agent/commit/3bace071bfadf2d2bec2ee048471a31ec920e3e8)
- [https://github.com/NousResearch/hermes-agent/pull/30917](https://github.com/NousResearch/hermes-agent/pull/30917)
- [https://github.com/NousResearch/hermes-agent/pull/31469](https://github.com/NousResearch/hermes-agent/pull/31469)
- [https://github.com/NousResearch/hermes-agent/releases/tag/v2026.6.5](https://github.com/NousResearch/hermes-agent/releases/tag/v2026.6.5)
- [https://www.vulncheck.com/advisories/hermes-agent-sensitive-file-permission-vulnerability-in-store-files](https://www.vulncheck.com/advisories/hermes-agent-sensitive-file-permission-vulnerability-in-store-files)

## Related threats

- [NousResearch hermes-agent resource exhaustion in resourceBufferFromUrl](https://junglewise.ai/threats/cve-2026-85107-nousresearch-hermes-agent-resource-exhaustion-in)
- [NousResearch hermes-agent server-side request forgery in Link Title Fetch](https://junglewise.ai/threats/cve-2026-85106-nousresearch-hermes-agent-server-side-request-forgery-in-link)
- [NousResearch hermes-agent authorization bypass in Session Management](https://junglewise.ai/threats/cve-2026-85105-nousresearch-hermes-agent-authorization-bypass-in-session)
- [NousResearch hermes-agent denial of service in MCP Tool](https://junglewise.ai/threats/cve-2026-84289-nousresearch-hermes-agent-denial-of-service-in-mcp-tool)
- [NousResearch hermes-agent denial of service in ACP Prompt Workflow](https://junglewise.ai/threats/cve-2026-84288-nousresearch-hermes-agent-denial-of-service-in-acp-prompt)