CVE-2026-104901
CVE-2026-104901 — MISP ID Translator: Unescaped Remote Event ID Enables Cross-Site Scripting via Linked Server
MISP contains a cross-site scripting (XSS) vulnerability in the ID Translator feature. When a user views the ID Translator page, the application queries linked (remote) MISP servers for corresponding event identifiers. The event ID returned by the remote server was rendered in the HTML output without proper output encoding. A malicious or compromised linked server could return a crafted event ID containing arbitrary HTML or JavaScript markup. This markup would be rendered in the browser of any user in the host organization who views the ID Translator page, enabling session hijacking, credential theft, or other client-side attacks. Preconditions: - The victim must be an authenticated user of the host MISP instance. - A linked server must be configured on the host instance. - The victim must navigate to the ID Translator page for a given event. Affected versions: <2.5.48.
Published Updated Sources: NVD, MISP (CNA), GitHub, SOCRadar CTI
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Exploit code
public exploit, none observed
EPSS
0%
ahead of 0% of scored CVEs
CVSS base
5.1
medium
Remediation
The vendor's own words where we have them.
The vulnerability is remediated by enforcing integer typing on the remote event ID at the point where it enters the application data structure in the controller, and by applying HTML output encoding (the h() helper) to all user-visible fields (remote_id, server_id) in both the default and Overmind-themed ID Translator views. This ensures that even if a remote server returns non-numeric or markup-laden data, it cannot be interpreted as HTML by the browser.
First 24 hours
Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.
- Identify exposed assets running affected vendor/product/version combinations.
- Prioritize based on EPSS, PoC availability, and external exposure.
- Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.
Affected scope
Vendor, product and version as the advisories word them.
| Vendor | Product | Versions | Status |
|---|---|---|---|
| MISP | MISP | 0 to < 2.5.48 | Vulnerable |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Scope
X
Attack Complexity
Low
Attack Vector
Network
Privileges Req
None
User Interaction
A
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 5.1 | CVSS 4.0 | medium | — | — | MISP (CNA) |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
What this weakness leads to
MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- Bypass Protection Mechanism
- Read Application Data
- Execute Unauthorized Code or Commands
Mitigation: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples of libraries and frameworks that make it easier to generate properly encoded output include Microsoft's Anti-XSS library, the OWASP ESAPI Encoding module, and Apache Wicket.
Weakness & attack patterns
- CWE-79Cross-site Scripting
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
Public exploit
Capability, not use: code existing is a different claim from anyone running it.
Repositories
1
Detection
Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.
- Prioritize edge telemetry for network-reachable MISP.
- Monitor for scanner or exploit-pattern traffic after 1 public PoC repositories were reported.
Timeline
What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.
- 2026
Added · CVSS 3.1 5.1 (AV:N)
Oct 2, 2026 · NVD
Initial · CVE published
Oct 2, 2026 · NVD
CVE published by MITRE.
Oct 2, 2026 · SOCRadar CTI
References
1 on the record
- github.com/MISP/MISP/commit/bd5e80c84
Exploit, Third Party Advisory, Mitre, NIST
Elsewhere on this site
- MISPevery CVE for this vendor
- Cross-site Scriptingsame class
- CWE-79other pages naming this weakness
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record1
What should defenders know first?
CVE-2026-104901 is MISP ID Translator: Unescaped Remote Event ID Enables Cross-Site Scripting via Linked Server, a medium vulnerability affecting MISP from MISP. The current evidence does not list it in CISA KEV, and the exploit status is: Active exploitation is not confirmed from current sources for CVE-2026-104901. Public exploit evidence is: 1 public PoC repositories reported; 0 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 5.1 describes technical severity, while EPSS 0% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.