CVE-2026-15311

LOW 3.5

NousResearch hermes-agent Matrix Adapter matrix.py MatrixAdapter._markdown_to_html cross site scripting

CVSS Score

3.5

EPSS Score

0.2%

EPSS Percentile

10th

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.

CWE	CWE-79 CWE-94
Vendor	nousresearch
Product	hermes-agent
Published	Jul 9, 2026
Last Updated	Jul 10, 2026

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CVSS v3 Breakdown

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

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Scope

Confidentiality

Integrity

Availability

Affected Versions

NousResearch / hermes-agent

2026.5.29.0 2026.5.29.1 2026.5.29.2

References

NVD ↗ CVE.org ↗ EPSS Data ↗

vuldb.com: https://vuldb.com/vuln/377247 vuldb.com: https://vuldb.com/vuln/377247/cti vuldb.com: https://vuldb.com/cve/CVE-2026-15311 vuldb.com: https://vuldb.com/submit/852843 github.com: https://github.com/NousResearch/hermes-agent/issues/42667 github.com: https://github.com/NousResearch/hermes-agent/pull/42759 github.com: https://github.com/NousResearch/hermes-agent/

Credits

🔍 Eric-d (VulDB User) VulDB CNA Team