CVE-2026-104900
MISP Stored XSS via Unescaped Count Field Value in Remote Event Preview Index
MISP contains a stored cross-site scripting (XSS) vulnerability in the index table rendering of the remote event preview. The count field template escaped the associated link URL but rendered the field value without HTML encoding. An attacker with the ability to create or modify events on a linked (remote) MISP server could craft an event identifier containing HTML or JavaScript markup. When a user on the local MISP instance views the remote event preview index, the unescaped value is rendered directly in the browser, allowing arbitrary script execution in the victim's session.
Preconditions:
-
A linked/remote MISP server is configured and connected to the local instance.
-
The attacker has sufficient access on the linked server to create or modify an event with a crafted identifier.
-
A victim user on the local instance views the remote event preview index page.
Impact:
-
Execution of arbitrary JavaScript in the context of the MISP web application.
-
Potential session hijacking, data exfiltration, or unauthorized actions performed on behalf of the authenticated user.
Affected versions: <2.5.48.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
MISP Stored XSS via Unescaped Count Field Value in Remote Event Preview Index
MISP contains a stored cross-site scripting (XSS) vulnerability in the index table rendering of the remote event preview. The count field template escaped the associated link URL but rendered the field value without HTML encoding. An attacker with the ability to create or modify events on a linked (remote) MISP server could craft an event identifier containing HTML or JavaScript markup. When a user on the local MISP instance views the remote event preview index, the unescaped value is rendered directly in the browser, allowing arbitrary script execution in the victim's session.
Preconditions:
-
A linked/remote MISP server is configured and connected to the local instance.
-
The attacker has sufficient access on the linked server to create or modify an event with a crafted identifier.
-
A victim user on the local instance views the remote event preview index page.
Impact:
-
Execution of arbitrary JavaScript in the context of the MISP web application.
-
Potential session hijacking, data exfiltration, or unauthorized actions performed on behalf of the authenticated user.
Affected versions: <2.5.48.
- Record
CVE-2026-104900- CVSS 4.0
- 5.3 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-91669
MISP contains a stored cross-site scripting (XSS) vulnerability in the index table rendering of the remote event preview. The count field template escaped the associated link URL but rendered the field value without HTML encoding. An attacker with the ability to create or modify events on a linked (remote) MISP server could craft an event identifier containing HTML or JavaScript markup. When a user on the local MISP instance views the remote event preview index, the unescaped value is rendered directly in the browser, allowing arbitrary script execution in the victim's session.
Preconditions:
-
A linked/remote MISP server is configured and connected to the local instance.
-
The attacker has sufficient access on the linked server to create or modify an event with a crafted identifier.
-
A victim user on the local instance views the remote event preview index page.
Impact:
-
Execution of arbitrary JavaScript in the context of the MISP web application.
-
Potential session hijacking, data exfiltration, or unauthorized actions performed on behalf of the authenticated user.
Affected versions: <2.5.48.
- Record
EUVD-2026-91669- CVSS 4.0
- 5.3 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-7mf5-g482-f646
MISP contains a stored cross-site scripting (XSS) vulnerability in the index table rendering of...
MISP contains a stored cross-site scripting (XSS) vulnerability in the index table rendering of the remote event preview. The count field template escaped the associated link URL but rendered the field value without HTML encoding. An attacker with the ability to create or modify events on a linked (remote) MISP server could craft an event identifier containing HTML or JavaScript markup. When a user on the local MISP instance views the remote event preview index, the unescaped value is rendered directly in the browser, allowing arbitrary script execution in the victim's session.
Preconditions:
-
A linked/remote MISP server is configured and connected to the local instance.
-
The attacker has sufficient access on the linked server to create or modify an event with a crafted identifier.
-
A victim user on the local instance views the remote event preview index page.
Impact:
-
Execution of arbitrary JavaScript in the context of the MISP web application.
-
Potential session hijacking, data exfiltration, or unauthorized actions performed on behalf of the authenticated user.
Affected versions: <2.5.48.
- Record
GHSA-7mf5-g482-f646- CVSS 4.0
- 5.3 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/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 - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
MISP contains a stored cross-site scripting (XSS) vulnerability in the index table rendering of the remote event preview. The count field template escaped the associated link URL but rendered the field value without HTML encoding. An attacker with the ability to create or modify events on a linked (remote) MISP server could craft an event identifier containing HTML or JavaScript markup. When a user on the local MISP instance views the remote event preview index, the unescaped value is rendered directly in the browser, allowing arbitrary script execution in the victim's session.
Preconditions:
-
A linked/remote MISP server is configured and connected to the local instance.
-
The attacker has sufficient access on the linked server to create or modify an event with a crafted identifier.
-
A victim user on the local instance views the remote event preview index page.
Impact:
-
Execution of arbitrary JavaScript in the context of the MISP web application.
-
Potential session hijacking, data exfiltration, or unauthorized actions performed on behalf of the authenticated user.
Affected versions: <2.5.48.
- Record
CVE-2026-104900- CVSS 4.0
- 5.3 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/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 - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
MISP Stored XSS via Unescaped Count Field Value in Remote Event Preview Index
MISP contains a stored cross-site scripting (XSS) vulnerability in the index table rendering of the remote event preview. The count field template escaped the associated link URL but rendered the field value without HTML encoding. An attacker with the ability to create or modify events on a linked (remote) MISP server could craft an event identifier containing HTML or JavaScript markup. When a user on the local MISP instance views the remote event preview index, the unescaped value is rendered directly in the browser, allowing arbitrary script execution in the victim's session.
Preconditions:
-
A linked/remote MISP server is configured and connected to the local instance.
-
The attacker has sufficient access on the linked server to create or modify an event with a crafted identifier.
-
A victim user on the local instance views the remote event preview index page.
Impact:
-
Execution of arbitrary JavaScript in the context of the MISP web application.
-
Potential session hijacking, data exfiltration, or unauthorized actions performed on behalf of the authenticated user.
Affected versions: <2.5.48.
- Record
CVE-2026-104900- CVSS 4.0
- 5.3 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
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-2026-104900 is a medium vulnerability (CVSS 5.3) in Misp, published October 2, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.36%, the 29th percentile. No source names a fixed version.