Altium Enterprise Server CVE-2026-11424

The attacker must hold valid authenticated credentials to the GraphQL service of Altium Enterprise Server (CVSS PR:L) and be able to reach its network-exposed GraphQL endpoint; no user interaction, no MFA bypass, and no non-default configuration are required because the vulnerable URL-handling behavior is present in default deployments prior to 8.1.1. Exploitation is limited in three concrete ways: (1) the request primitive is restricted to HTTP GET only, so POST-based metadata APIs and SSRF-to-RCE chains requiring header injection are out of reach; (2) no custom headers can be sent, which blocks AWS IMDSv2 token retrieval and any internal service requiring authentication headers; and (3) Altium 365 tenants are not exploitable because the SaaS instance has already been patched server-side.

The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N) score of 8.3 is consistent with the described primitive: network-reachable, low complexity, low privileges required, no user interaction, high confidentiality impact on both the vulnerable component and a subsequent (scope-changed) system, with no integrity or availability impact. This is a real priority for organizations running Altium Enterprise Server because the PR:L barrier is low - any authenticated user of the GraphQL service qualifies - and the SC:H rating reflects the ability to pivot into internal infrastructure or harvest cloud metadata (potentially including IAM credentials on improperly hardened cloud hosts). Mitigating factors: the request primitive is restricted to HTTP GET with no custom headers, which limits exploitation of metadata services that require special headers (e.g., AWS IMDSv2's X-aws-ec2-metadata-token requirement) and prevents direct interaction with non-HTTP protocols. EPSS score was not provided in the input, the CVE is not in CISA KEV, and no POC has been published, so exploitation appears opportunistic rather than mass-automated, but the vendor-reported nature and clean exploitability profile warrant prompt patching.

An attacker with valid low-privilege credentials to Altium Enterprise Server (e.g., a contractor account or a phished engineer) submits a crafted GraphQL request supplying a URL such as http://169.254.169.254/latest/meta-data/iam/security-credentials/ or http://internal-gitlab.corp.local/. The server issues the outbound GET and returns the response body, giving the attacker cloud IAM credentials or an enumeration of internal services. No public POC has been published, but the primitive is straightforward enough to reproduce from the advisory description.