CVE-2026-5799: Ontime Authorization Bypass via User-Controlled Key (CVSS 7.5)

Technical summary

CVE-2026-5799 is an authorization bypass vulnerability rooted in improper handling of user-controlled keys (CWE-639: Authorization Through User-Controlled Key). The flaw permits attackers to circumvent access controls by tampering with trusted identifiers. With a network-accessible attack vector, no authentication required, and low attack complexity, threat actors can exploit this remotely to read confidential data. The vulnerability carries a CVSS v3.1 score of 7.5 (HIGH), reflecting the high confidence impact on confidentiality without requiring user interaction or special privileges.

Business impact

This vulnerability exposes sensitive data to unauthorized disclosure. Organizations relying on Ontime for user access control face immediate risk of data exfiltration and potential compliance violations if customer, financial, or operational information is accessed without authorization. The ease of exploitation—no authentication, no user interaction required—means attackers can operate silently, increasing the window of undetected exposure. This directly undermines data confidentiality and trust in the platform's security posture.

Affected systems

Idvlabs Software and Consulting Services Inc. Ontime is affected through version 04052026 (April 5, 2026). Organizations should inventory all deployments of Ontime, particularly those internet-facing or accessible from untrusted networks, and prioritize patching immediately. Verify your specific version against the vendor's official advisory to confirm scope.

Exploitability

This vulnerability is readily exploitable. It requires only network access, no authentication, and low complexity—attackers need no special tools or deep technical knowledge. The attack can be performed by an unauthenticated remote attacker. No user interaction or special system conditions are necessary. This combination makes it a high-priority target for threat actors scanning for quick wins.

Remediation

Apply the latest security patch from Idvlabs Software and Consulting Services Inc. as soon as it becomes available. Until patching is possible, implement network segmentation to restrict access to Ontime instances and enforce strict firewall rules limiting inbound connections. Consider deploying Web Application Firewall (WAF) rules to detect and block unauthorized identifier manipulation attempts. Monitor access logs for suspicious patterns of identifier reuse or tampering.

Patch guidance

Contact Idvlabs Software and Consulting Services Inc. directly or check their official security advisories for patch availability and version details. Given the severity and ease of exploitation, prioritize patching within 24–72 hours of availability in your change management process. Test patches in a non-production environment first, but do not delay deployment to production given the network-exploitable nature and lack of authentication requirement.

Detection guidance

Monitor application logs and network traffic for patterns indicative of identifier manipulation: repeated failed authorization attempts, successful access using mismatched or invalid identifiers, or unusual cross-user data access patterns. Deploy request inspection rules to flag anomalous user-controlled key values. Review access logs for any discrepancies between authenticated users and the identifiers they used. Implement alerting on unexpected privilege escalation or sensitive data access by unauthenticated sessions.

Why prioritize this

This vulnerability combines ease of exploitation (unauthenticated, no user interaction, network-accessible) with direct confidentiality impact (HIGH), earning a CVSS score of 7.5. The low barrier to entry and immediate risk to sensitive data make it attractive to opportunistic attackers and suitable for automated scanning. It should be patched before less urgent vulnerabilities and monitored aggressively during remediation windows.

Risk score, explained

The CVSS v3.1 score of 7.5 reflects: (1) Network Attack Vector—remote exploitation possible; (2) Low Attack Complexity—no special conditions or tools needed; (3) No authentication required; (4) No user interaction; (5) HIGH confidentiality impact—sensitive data can be read; (6) Integrity and Availability remain unaffected. The absence of ransomware designation does not lower the risk; data exfiltration alone justifies urgent remediation. Not currently listed on CISA's Known Exploited Vulnerabilities (KEV) catalog, though organizations should monitor for active exploitation intelligence.

Frequently asked questions