CVE-2026-18369
Description
A flaw was found in Dogtag PKI's ACME responder where the HTTP-01 challenge validator accepts IP address literals as dns identifiers and follows HTTP redirects without validating that the target is a public address. An unauthenticated ACME account holder can exploit this to perform server-side request forgery (SSRF), making the Dogtag server send HTTP GET requests to internal network services. With the InMemory database backend, the response body of internal targets is disclosed to the attacker through the ACME challenge error.
Statement
Red Hat rates this Moderate because exploitation is limited to HTTP GET requests (no integrity impact), the attacker cannot read internal responses on production-supported backends (low confidentiality impact), and the ACME responder must be explicitly deployed. The Scope is Changed (S:C) because the ACME responder causes the Dogtag server to make outbound requests to services outside its own trust boundary, but the actual information gained on supported configurations is limited to network topology probing. While the SSRF is GET-only and does not directly allow data modification, administrators should be aware that internal services reachable from the Dogtag host which perform actions on HTTP GET (such as cloud instance metadata endpoints that issue temporary credentials) could be indirectly affected.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.8 | N/A | 5.8 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Changed | N/A | Changed |
| Confidentiality | Low | N/A | Low |
| Integrity Impact | None | N/A | None |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Application Data
Integrity
Technical Impact: Execute Unauthorized Code or Commands
Access Control
Technical Impact: Bypass Protection Mechanism
By providing URLs to unexpected hosts or ports, attackers can make it appear that the server is sending the request, possibly bypassing access controls such as firewalls that prevent the attackers from accessing the URLs directly. The server can be used as a proxy to conduct port scanning of hosts in internal networks, use other URLs such as that can access documents on the system (using file://), or use other protocols such as gopher:// or tftp://, which may provide greater control over the contents of requests.
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