MISP Unauthenticated Blind SSRF via XML Body Processing
Summary
| CVE | CVE-2026-95679 |
|---|---|
| State | PUBLISHED |
| Assigner | CIRCL |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-22 14:17:22 UTC |
| Updated | 2026-09-22 16:18:22 UTC |
| Description | MISP's RequestHandlerComponent automatically decodes XML request bodies on all write requests. The underlying Xml::build() library contains a logic error in its readFile guard condition (readFile && http || https), where PHP operator precedence causes the https branch to bypass the readFile check entirely. As a result, a request body containing a bare HTTPS URL is treated as a locator and fetched by the server. Because the cspReport endpoint accepts XML content type and is unauthenticated by design, an unauthenticated remote attacker can send a POST request with a crafted XML body to cause the MISP server to issue an outbound HTTPS request to an arbitrary target reachable from the server. The attacker does not receive the response body, but can use the vulnerability to probe internal services, trigger actions on internal HTTPS endpoints, or perform timing-based reconnaissance of the server's network environment. The vulnerability affects any MISP deployment where the cspReport endpoint is reachable and the server has network access to internal or external HTTPS services. |
Risk And Classification
Primary CVSS: v4.0 6.9 MEDIUM from 5a6e4751-2f3f-4070-9419-94fb35b644e8
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/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
Problem Types: CWE-20 | CWE-918 | CWE-918 CWE-918 Server-Side Request Forgery (SSRF) | CWE-20 CWE-20 Improper Input Validation
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | 5a6e4751-2f3f-4070-9419-94fb35b644e8 | Secondary | 6.9 | MEDIUM | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | CVSS | 6.9 | MEDIUM | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N |
CVSS v4.0 Breakdown
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/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
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/MISP/MISP/commit/716fc49d3 | 5a6e4751-2f3f-4070-9419-94fb35b644e8 | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Niels Teusink of Eye Security (en)
CNA: iglocska (en)
CNA: Claude Opus 5 (1M context) (en)
Additional Advisory Data
Solutions
CNA: The fix introduces a custom XML input type handler in AppController::beforeFilter() that validates the request body contains an XML document marker (the < character) before passing it to the XML decoder. If the body does not contain <, it returns an empty array, preventing the Xml::build() locator/fetch code path from being reached regardless of the vendored library's internal guard logic. This ensures only actual XML documents are processed, eliminating the SSRF vector.