Low 3.5Published Jul 9, 2026

CVE-2026-15311NousResearch hermes-agent Matrix Adapter matrix.py MatrixAdapter._markdown_to_html cross site scripting

Updated under an hour ago (Oct 27, 2026, 8:10 AM ET)

Does this affect you?

It affects NousResearch hermes-agent. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for NousResearch hermes-agent

Exploited in the last 30 days

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.

CVSS: 3.5 LOW (v3.1, CNA)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
Weakness (CWE): CWE-79, CWE-94
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulDB
NVD analysis: Deferred
Record last updated: Jul 10, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

NousResearch hermes-agent nousresearch:hermes-agent	2026.5.29.0; 2026.5.29.1; 2026.5.29.2	CNA record

References

References

https://vuldb.com/vuln/377247	vdb-entry, technical-description
https://vuldb.com/vuln/377247/cti	signature, permissions-required
https://vuldb.com/cve/CVE-2026-15311	third-party-advisory
https://vuldb.com/submit/852843	third-party-advisory
https://github.com/NousResearch/hermes-agent/issues/42667	exploit, issue-tracking
https://github.com/NousResearch/hermes-agent/pull/42759	issue-tracking, patch
https://github.com/NousResearch/hermes-agent/	product

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.