CVE-2026-86419
HIGH 7 ALL-YEARSAffected versions of MISP contain insufficient validation of server-side outbound HTTP destinations in feed retrieval and TAXII discovery functionality. In feed processing, redirects were followed without validating the redirect scheme or destination. The original request headers were reused across redirect hops, meaning authentication headers or API credentials configured for a feed could be forwarded to a different host. Redirects could also target internal network resources, resulting in SSRF. The fix adds redirect validation, blocks internal destinations for cross-host redirects, strips configured feed credentials before following redirects to another host, and pins validated DNS results to prevent re-resolution after validation. The TAXII discovery endpoint had a related incomplete SSRF defense. It used gethostbyname() and compared the result against only a few literal addresses. This missed cases including IPv6 loopback (::1), numeric host encodings such as 0x7f000001, and potentially multiple DNS records. The fix moves TAXII discovery to the shared URL egress validator. Together, these commits harden MISP's outbound URL handling against alternate-address representations, DNS-related bypasses, unsafe redirects, internal-host access, and cross-host credential forwarding. Version affected: ≤2.5.45
Severe if exploited (CVSS 7), but no confirmed exploitation. Patch on a normal cadence.
Exploitation likelihood
0.4%chance of exploitation in 30 days · 34th percentile
Impact if exploited
7CVSS 4.0 · HIGH · CNA
- ConfidentialityLow
- IntegrityLow
- AvailabilityHigh
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ⚠Privileges: Requires an admin / high-privilege account
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
- ⚠Requirements: Specific conditions must be present
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
No public exploit or proof-of-concept code is catalogued for this CVE (no ExploitDB, Nuclei, or CISA-KEV entry). It may still exist — search GitHub or check the references below.
Weakness (CWE)
- CWE-918: Server-Side Request Forgery (SSRF)
- CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:H/SC:H/SI:N/SA:N
Known Affected Software Configurations
| Vendor | Product | Version range |
|---|---|---|
| Misp Project | Misp | ≤ 2.5.45 |
All CVSS metrics
- HIGH 7 v4.0 · CNA Primary
CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:H/SC:H/SI:N/SA:N - HIGH 7 v4.0 · NVD Secondary
CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:H/SC:H/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 - CRITICAL 9.1 v3.1 · NVD Primary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H