Executive brief
MISP is an open-source threat intelligence platform used by organizations to share and analyze malware and security indicators. The vulnerability allows an attacker to exploit feed retrieval and TAXII discovery endpoints to access internal network resources, bypass server-side access controls, and steal authentication credentials configured for feed sources. An attacker could redirect legitimate feed requests to internal systems or use crafted DNS names to map to internal IP addresses, potentially exposing sensitive threat intelligence or gaining access to internal infrastructure.
Technical details
This is a server-side request forgery (SSRF) vulnerability with credential exposure in MISP's feed retrieval and TAXII discovery features. In feed processing, HTTP redirects were followed without validating the redirect scheme or destination, and original request headers (including authentication credentials) were reused across redirect hops, allowing them to be forwarded to attacker-controlled hosts. The TAXII discovery endpoint used incomplete host validation that only compared resolved IPs against a few literal addresses, missing IPv6 loopback (::1), alternate numeric encodings (0x7f000001), and DNS records with multiple IPs. An attacker can craft malicious feeds or TAXII configurations to trigger requests to internal network resources. The fix adds redirect validation with scheme checking, blocks internal destinations on cross-host redirects, strips feed credentials before following redirects, and moves TAXII discovery to a shared egress validator with comprehensive address-space validation and DNS-pinning.
Affected products
- MISP MISP ≤2.5.45
Timeline
- 2026-09-07: disclosed
- 2026-08-19: patched: Security fixes committed to repository