CVE-2026-15311

Severity CVSS v4.0:

LOW

Type:

CWE-79 Cross-Site Scripting (XSS)

Publication date:

10/07/2026

Last modified:

10/07/2026

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.

Impact

Vector 4.0

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 CVSS v4.0 Severity and Metrics:

Base Score: 2.00 LOW
Vector: 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

Attack Vector (AV): Network
Attack Complexity (AC): Low
Attack Requirements (AT): None
Privileges Required (PR): Low
User Interaction (UI): Passsive
Confidentiality (VC): None
Integrity (VI): Low
Availability (VA): None
Confidentiality (SC): None
Integrity (SI): None
Availability (SA): None
Exploit Maturity (E): POC

Base Score 4.0

2.00

Severity 4.0

LOW

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N CVSS v3.1 Severity and Metrics:

Base Score: 3.50 LOW
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): Required
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): Low
Availability (A): None

Base Score 3.x

3.50

Severity 3.x

LOW

Vector 2.0

AV:N/AC:L/Au:S/C:N/I:P/A:N CVSS v2.0 Severity and Metrics:

Base Score: 4.00 MEDIUM
Vector: AV:N/AC:L/Au:S/C:N/I:P/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Authentication (Au): Single
Confidentiality (C): None
Integrity (I): Physical
Availability (A): None

Base Score 2.0

4.00

Severity 2.0

MEDIUM

CVE-2026-15311

Description

Impact

References to Advisories, Solutions, and Tools