--- id: "CVE-2026-115813" kind: "vulnerability" aliases: ["CVE-2026-115813"] title: "AWS Multi Model Server: model download path enables server-side request forgery" severity: "medium" cvss: 6.9 epss: 0.0034 exploited: false status: "open" category: "ai-tooling" products: [] ecosystems: [] tags: ["ai-tooling", "aws", "docker", "lab-disclosure", "ml-serving", "multi-model-server", "self-hosted"] not_affected_if: ["external-urls-not-passed", "management-interface-loopback-only", "not-running-mms"] published_at: "2026-10-23T00:00:00+00:00" first_seen_at: "2026-10-23T21:57:34+00:00" updated_at: "2026-10-25T12:38:50+00:00" sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-115813", "first_seen_at": "2026-10-23T21:57:34+00:00"}, {"source": "lab", "url": "https://aws.amazon.com/security/security-bulletins/rss/2026-148-aws/", "first_seen_at": "2026-10-24T19:43:43+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-115813", "first_seen_at": "2026-10-25T12:38:50+00:00"}] --- # AWS Multi Model Server: model download path enables server-side request forgery Amazon Web Services Multi Model Server, an end-of-life tool for serving ML models, lets its unauthenticated management interface be directed to make requests to unintended network destinations. An attacker who can reach that interface can use the server to probe internal services. _Summary, check and fix written by a model from the sources; labelled as such._ ## How to check - Check whether `multi-model-server` is installed, for example with `pip show multi-model-server` or by looking for the MMS image in Docker Hub deployments. - Check the installed version; the bulletin says all released versions up to `1.1.11` are affected. - Check whether the management interface (default port 8081) is bound to a non-loopback address or reachable from untrusted networks. ## Fix - No fixed version exists; AWS says Multi Model Server is end of life and recommends migrating to a supported model-serving solution. - Bind the management interface to loopback (`127.0.0.1`) where the configuration allows it. - Do not pass externally supplied URLs to the model-download path. - In SageMaker-style configurations where management cannot be moved to loopback, restrict the serving port to trusted callers while migrating. ## Mitigated for you by - Team (workaround): covers Management interface reachable only from loopback, so it is not exposed to untrusted networks Limits: Not available where management and inference share one port (SageMaker-style configuration); there, moving management to loopback also disables model loading Still: Bind the management interface to the loopback address; in shared-port deployments, ensure the serving port is reachable only by trusted callers https://aws.amazon.com/security/security-bulletins/rss/2026-148-aws/ - Team (workaround): covers Model download path when no externally supplied URLs are passed to it Limits: Does not address the archive extraction issue (CVE-2026-115812); not available in shared-port SageMaker-style configuration except by restricting who can reach the serving port Still: Do not pass externally supplied URLs to the model-download path https://aws.amazon.com/security/security-bulletins/rss/2026-148-aws/ ## Timeline - 2026-10-23T21:57:34+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-115813 - 2026-10-24T19:43:43+00:00 lab https://aws.amazon.com/security/security-bulletins/rss/2026-148-aws/ — AWS: CVE-2026-115812 and CVE-2026-115813: Issue in Amazon Web Services Multi Model Server - 2026-10-25T12:38:50+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-115813 ## Documents - [advisory] AWS bulletin 2026-148-AWS: CVE-2026-115812 and CVE-2026-115813 Multi Model Server https://aws.amazon.com/security/security-bulletins/2026-148-aws/ - [advisory] AWS: CVE-2026-115812 and CVE-2026-115813: Issue in Amazon Web Services Multi Model Server https://aws.amazon.com/security/security-bulletins/rss/2026-148-aws/ ## From the sources CVE-2026-115812 and CVE-2026-115813: Issue in Amazon Web Services Multi Model Server ### CVE-2026-115812 and CVE-2026-115813: Issue in Amazon Web Services Multi Model Server Bulletin ID: 2026-148-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 10/23/2026 10:30 AM PDT Description: Amazon Web Services Multi Model Server (MMS) is an open source tool for serving machine learning models for inference. It was published by AWS on GitHub, PyPI, and Docker Hub, and reached end of life; its source repository has been archived and read-only since November 20, 2025. We identified the following issues in MMS: - CVE-2026-115812: An issue in model archive extraction could allow a crafted model archive to write files outside the intended directory, potentially resulting in code execution with the privileges of the MMS process. - CVE-2026-115813: An issue in the model download path could allow the MMS management interface to be directed to make requests to unintended network destinations. In both cases, the MMS management interface does not require authentication. Deployments that bind this interface to a network-accessible address are at increased risk. Because MMS has reached end of life and is no longer maintained, we recommend that users migrate to a supported model-serving solution. Impacted versions: <=1.1.11 (all released versions) Resolution: Multi Model Server is end of life and no fixed version is available or planned on any distribution channel. We recommend that customers discontinue use of Multi Model Server and migrate to a supported model serving solution. Customers who maintain forked or derivative code should apply equivalent changes themselves: reject any archive entry whose resolved path falls outside the extraction directory, and restrict the model-download path to an explicit allowlist of permitted URLs. Workarounds: Where a deployment binds the inference and management interfaces to separate ports, bind the management interface to the loopback address so it is not reachable from untrusted networks, and do not pass externally supplied URLs to the model-download path. This workaround is not available in every configuration. The configuration shipped for SageMaker-style deployments binds the management interface to all addresses on the same port as inference, so management cannot be moved to loopback there without also disabling model loading. Deployments in that configuration should prioritize migration, and in the interim should ensure the serving port is reachable only by trusted callers. References: - CVE-2026-115812 - CVE-2026-115813 Acknowledgement: We would like to thank Sujal Tuladhar for collaborating on this issue through the coordinated vulnerability disclosure process. Please email aws-security@amazon.com with any security questions or concerns. --- _Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_