ServiceNow AI Platform: Three CVSS 10.0 Flaws — Unauth Arbitrary Code and SQL

ServiceNow patched four ServiceNow AI Platform flaws on 27 August. CVE-2026-18885 (GraphQL code injection), CVE-2026-18886 (image-upload handler ACL bypass), and CVE-2026-74820 (dynamic ORDER BY SQL injection) all score CVSS 10.0 and are remotely triggerable with no auth. 85% of Fortune 500 use ServiceNow; self-hosted customers must manually upgrade to the latest Xanadu/Yokohama/Zurich/Australia patches.

Incident Overview

ServiceNow's August security bulletin, published 27 August 2026, disclosed fixes for four vulnerabilities in the ServiceNow AI Platform (also Now Platform). Three score a perfect 10.0 under CVSS 4.0: code injection in the GraphQL Composite Data API (CVE-2026-18885), an access-control flaw in the system-configuration image-upload handler (CVE-2026-18886), and SQL injection via a dynamic-schema ORDER BY clause (CVE-2026-74820). All three: no credentials, no user interaction, low attack complexity, network-reachable. Confidentiality, integrity, and availability of the affected component and downstream systems: fully compromised. Fourth: CVE-2026-6876, Now Platform sandbox escape (CVSS 4.0 8.7), also arbitrary code execution.

ServiceNow auto-applied patches on cloud-hosted instances. All self-hosted instances and customers in partner environments must upgrade manually. ServiceNow co-founder team has not disclosed known in-the-wild exploitation. As a CVE Numbering Authority, after self-scoring, these issues are in global vulnerability-management scope.

Technical Details

• CVE-2026-18885 (CVSS 10.0): code injection in the GraphQL Composite Data API. Unauthenticated users execute arbitrary code via crafted requests, then access or modify instance data;
• CVE-2026-18886 (CVSS 10.0): system-configuration image-upload handler lacks access-control checks. Unauthenticated users upload arbitrary files, create/modify instance data, escalate to admin;
• CVE-2026-74820 (CVSS 10.0): dynamic-schema ORDER BY clause concatenates SQL fragments. Unauthenticated users execute arbitrary SQL — read, modify, delete against the underlying database;
• CVE-2026-6876 (CVSS 8.7): Now Platform sandbox escape. Attackers break instance isolation and execute arbitrary code.

Shared CVSS 4.0 vector for the three 10.0 issues: AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H. Network-reachable, no privileges, no user interaction, full impact on the component and downstream systems.

Impact Scope

Affected versions (per official advisory):

• Xanadu: any version earlier than Patch 11 Hot Fix 7a;
• Yokohama: any version earlier than Patch 12 Hot Fix 3b or Patch 13 Hot Fix 4;
• Zurich: any version earlier than Patch 7b Hot Fix 3, Patch 8 Hot Fix 5, Patch 9 Hot Fix 6, Patch 10 Hot Fix 2m/3, Patch 11, or Patch 12;
• Australia: any version earlier than Patch 2 Hot Fix 3, Patch 3 Hot Fix 2, Patch 3m, Patch 4, or Patch 5.

Customer base: ServiceNow is large — roughly 85% of Fortune 500 companies run Now Platform. ServiceNow typically couples deeply with Active Directory, ERP, HR, and customer-service systems. Compromise of a single instance often becomes a pivot for cross-system lateral movement and ransomware delivery.

Remediation

• Immediately upgrade self-hosted instances to the latest patch versions above;
• After upgrade, restart the workflow execution engine and reload compiled scripts. Verify Web Services and GraphQL interface access logs for anomalies;
• Enable security baselines such as instance_hardening and restrict_outbound_http. Restrict OUTBOUND HTTP. Restrict executable roles on sys_db_action. Enable high security level (High in Security levels);
• Check sys_audit for unauthorized GraphQL, image-upload, and SQL schema query access. Roll back suspicious transactions if needed;
• If you cannot upgrade yet, disable all external access to /api/now/graphql and /api/now/v2/image/upload at the reverse proxy/WAF.

References

• ServiceNow KB3152242 original advisory
• CVE official record CVE-2026-74820
• CVE official record CVE-2026-18885
• CVE official record CVE-2026-18886
• The CyberSignal: analysis of three unauthenticated CVSS 10.0 flaws in ServiceNow AI Platform