CVE-2026-9353NousResearch hermes-agent Skills Guard Multi-Word Prompt skills_guard.py injection
- 6.9MediumCVSS base score
- 0.30%Exploitation in 30 daysEPSS · top 76% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
A security vulnerability has been detected in NousResearch hermes-agent up to 2026.4.23. Impacted is an unknown function of the file agent/skills_guard.py of the component Skills Guard Multi-Word Prompt Handler. The manipulation of the argument THREAT_PATTERNS leads to injection. Remote exploitation of the attack is possible. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits1
References tagged exploit1 reference
Timeline
ID reserved
By VulDB
- 1 day later
· 1 day later
Published
- 2 days later
· 2 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulDBCNA (assigner) | 4.0 | Medium6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P |
| VulDBCNA (assigner) | 3.1 | High7.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R |
| VulDBCNA (assigner) | 3.0 | High7.3 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R |
| VulDBCNA (assigner) | 2.0 | High7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P/E:POC/RL:ND/RC:UR |
| NVDNVD · Deferred | 4.0 | Medium5.5 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.30% · top 76% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.9.
Affected products
- affected 2026.4.0
- affected 2026.4.1
- affected 2026.4.2
- affected 2026.4.3
- affected 2026.4.4
- affected 2026.4.5
- affected 2026.4.6
- affected 2026.4.7
- affected 2026.4.8
- affected 2026.4.9
- affected 2026.4.10
- affected 2026.4.11
- affected 2026.4.12
- affected 2026.4.13
- affected 2026.4.14
- affected 2026.4.15
- affected 2026.4.16
- affected 2026.4.17
- affected 2026.4.18
- affected 2026.4.19
- affected 2026.4.20
- affected 2026.4.21
- affected 2026.4.22
- affected 2026.4.23
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- PyPIhermes-agentGHSA-238w-f66p-w349 (opens in a new tab)
References
References4
- VDB-365316 | NousResearch hermes-agent Skills Guard Multi-Word Prompt skills_guard.py injection (opens in a new tab)vdb-entrytechnical-description
- VDB-365316 | CTI Indicators (IOB, IOC, TTP, IOA) (opens in a new tab)signaturepermissions-required
- Submit #812216 | NousResearch hermes-agent 2026.4.23 Injection (CWE-74) (opens in a new tab)third-party-advisory
- https://gist.github.com/YLChen-007/82a3539d6358842e69dfaef0a9fcf14a (opens in a new tab)exploit
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-31567 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-238w-f66p-w349 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-9353)Record last updated .