CVE-2026-9366
NousResearch hermes-agent prompt_builder.py _scan_context_content injection
A vulnerability was found in NousResearch hermes-agent 2026.4.23. The impacted element is the function _scan_context_content of the file agent/prompt_builder.py. The manipulation results in injection. The attack may be performed from remote. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
6.9
NousResearch hermes-agent prompt_builder.py _scan_context_content injection
A vulnerability was found in NousResearch hermes-agent 2026.4.23. The impacted element is the function _scan_context_content of the file agent/prompt_builder.py. The manipulation results in injection. The attack may be performed from remote. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.
- Record
CVE-2026-9366- CVSS 4.0
- 6.9 Medium
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 - CVSS 3.1
- 7.3 High
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 - CVSS 3.0
- 7.3 High
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 - CVSS 2.0
- 7.5
AV:N/AC:L/Au:N/C:P/I:P/A:P/E:POC/RL:ND/RC:UR - Weakness
- CWE-74, CWE-707
- Updated
- 2026-11-02
EUVDEUVD-2026-31580
6.9
A vulnerability was found in NousResearch hermes-agent 2026.4.23. The impacted element is the function _scan_context_content of the file agent/prompt_builder.py. The manipulation results in injection. The attack may be performed from remote. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.
- Record
EUVD-2026-31580- CVSS 4.0
- 6.9 Medium
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-pgp4-xr4j-h5cg
5.5
hermes-agent has an Injection issue
A vulnerability was found in NousResearch hermes-agent 2026.4.23. The impacted element is the function _scan_context_content of the file agent/prompt_builder.py. The manipulation results in injection. The attack may be performed from remote. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.
- Record
GHSA-pgp4-xr4j-h5cg- CVSS 4.0
- 5.5 Medium
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 - CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-74
- Updated
- 2026-11-02
NVD
5.5
A vulnerability was found in NousResearch hermes-agent 2026.4.23. The impacted element is the function _scan_context_content of the file agent/prompt_builder.py. The manipulation results in injection. The attack may be performed from remote. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.
- Record
CVE-2026-9366- CVSS 4.0
- 5.5 Medium
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 - CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-74, CWE-707
- Updated
- 2026-11-02
OSVGHSA-pgp4-xr4j-h5cg
5.5
hermes-agent has an Injection issue
A vulnerability was found in NousResearch hermes-agent 2026.4.23. The impacted element is the function _scan_context_content of the file agent/prompt_builder.py. The manipulation results in injection. The attack may be performed from remote. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.
- Record
GHSA-pgp4-xr4j-h5cg- CVSS 4.0
- 5.5 Medium
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 - CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-74
- Updated
- 2026-11-02
OSVPYSEC-2026-2514
5.5
hermes-agent has an Injection issue
A vulnerability was found in NousResearch hermes-agent 2026.4.23. The impacted element is the function _scan_context_content of the file agent/prompt_builder.py. The manipulation results in injection. The attack may be performed from remote. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.
- Record
PYSEC-2026-2514- CVSS 4.0
- 5.5 Medium
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 - CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
hermes-agentPyPI |
before 0.15.0 | 0.15.0 |
hermes-agentPyPI |
before 0.15.0, plus listed versions 0.13.00.14.0 |
0.15.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-9366 is a medium vulnerability (CVSS 6.9) in Nousresearch Hermes-agent, published May 24, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.30%, the 23rd percentile. Fixed in hermes-agent 0.15.0.
References
vuldb.com/vuln/365329
vuldb.com/vuln/365329/cti
vuldb.com/submit/812227
gist.github.com/YLChen-007/581fd92de5548fbaacb2092e848a75cc
nvd.nist.gov/vuln/detail/CVE-2026-9366
github.com/NousResearch/hermes-agent/commit/0dee92df22bdc0cfbcad90ca954aa14916f018de
github.com/advisories/GHSA-pgp4-xr4j-h5cg
github.com/NousResearch/hermes-agent
pypi.org/project/hermes-agent