Vulnerability · Published Sep 7, 2026 · Assigned by CIRCL

CVE-2026-86419MISP Insufficient Outbound URL Validation Allows SSRF and Credential Disclosure via Feed Redirects and TAXII Discovery

High 7.0

In plain English

A high-severity server-side request forgery in MISP from MISP. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 36% of all known vulnerabilities).

Severity (CVSS 4.0)7.0High
Exploit odds (30 days)0.4%top 63.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Affected 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

Affected products (as reported)

VendorProductVersions
MISP MISP 0 – through 2.5.45

Weakness: CWE-918, CWE-200 · 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

References