CVE-2026-15311
NousResearch hermes-agent Matrix Adapter matrix.py MatrixAdapter._markdown_to_html cross site scripting
- State
- Published
- Severity
- 5.1 Medium
- Published
- Jul 9, 2026
- Updated
- Jul 10, 2026
- Reserved
- Jul 9, 2026
Description
A vulnerability was identified in NousResearch hermes-agent up to 2026.5.29.2. Affected by this issue is the function MatrixAdapter._markdown_to_html of the file gateway/platforms/matrix.py of the component Matrix Adapter. Such manipulation leads to cross site scripting. The attack can be executed remotely. The exploit is publicly available and might be used. The pull request to fix this issue awaits acceptance.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 5.1 Medium | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P | VulDB |
| 3.1 | 3.5 Low | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:C | VulDB |
| 3.0 | 3.5 Low | CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:C | VulDB |
| 2.0 | 4.0 Medium | AV:N/AC:L/Au:S/C:N/I:P/A:N/E:POC/RL:ND/RC:C | VulDB |
Weaknesses
Affected Products
| Product | Versions |
|---|---|
hermes-agentNousResearch |
|
References
- VDB-377247 | NousResearch hermes-agent Matrix Adapter matrix.py MatrixAdapter._markdown_to_html cross site scriptingvdb-entrytechnical-description
- VDB-377247 | CTI Indicators (IOB, IOC, TTP, IOA)signaturepermissions-required
- CVE-2026-15311 | CVE Analysis and Reportthird-party-advisory
- Submit #852843 | NousResearch hermes-agent 2026.5.29.2 Cross-site Scripting (CWE-79)third-party-advisory
- https://github.com/NousResearch/hermes-agent/issues/42667exploitissue-tracking
- https://github.com/NousResearch/hermes-agent/pull/42759issue-trackingpatch
- https://github.com/NousResearch/hermes-agent/product
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