Raw vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/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:XSummary
CVE-2026-27945 is a low-severity SSRF (CWE-918) vulnerability in Zitadel Zitadel. Its CVSS base score is 2.1 (Low).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 13th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to AC-4 (Information Flow Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-8793
Vulnerability Data
ZITADEL is an open source identity management platform. Zitadel Action V2 (introduced as early preview in 2.59.0, beta in 3.0.0 and GA in 4.0.0) is a webhook based approach to allow developers act on API request to Zitadel and customize…
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flows such the issue of a token. Zitadel's Action target URLs can point to local hosts, potentially allowing adversaries to gather internal network information and connect to internal services. When the URL points to a local host / IP address, an adversary might gather information about the internal network structure, the services exposed on internal hosts etc. This is sometimes called a Server-Side Request Forgery (SSRF). Zitadel Actions expect responses according to specific schemas, which reduces the threat vector. The patch in version 4.11.1 resolves the issue by checking the target URL against a denylist. By default localhost, resp. loopback IPs are denied. Note that this fix was only released on v4.x. Due to the stage (preview / beta) in which the functionality was in v2.x and v3.x, the changes that have been applied to it since then and the severity, respectively the actual thread vector, a backport to the corresponding versions was not feasible. Please check the workaround section for alternative solutions if an upgrade to v4.x is not possible. If an upgrade is not possible, prevent actions from using unintended endpoints by setting network policies or firewall rules in one's own infrastructure. Note that this is outside of the functionality provided by Zitadel.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.3.6V1.5.3V5.3.2V10.4.7
Mitigating Controls (NIST 800-53 r5) AI
Information flow enforcement can restrict which destinations the server is allowed to contact on behalf of users.
Input validation directly stops untrusted URLs from being accepted and fetched without destination checks.
Boundary protection limits the network reach of server-initiated requests even if SSRF occurs.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure development practices directly include input validation and destination allow-listing that prevent SSRF.
Runtime monitoring of web applications and services can detect anomalous outbound requests indicative of SSRF.
Vulnerability identification processes can discover and record SSRF flaws in web applications.
Network segmentation and egress controls can limit the damage from successful SSRF requests.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Operational threat data describing SSRF campaigns can be used to tighten outbound-request allow-lists and detection rules before attackers exploit them.