CVE-2026-66249 in iControl
Summary
by MITRE • 10/01/2026
iControl is affected by a Missing Secure Attribute vulnerability, which could allow an attacker to intercept cookies transmitted over unencrypted HTTP connections, enabling the unauthorized extraction of sensitive information such as session identifiers.
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Analysis
by VulDB Data Team • 10/01/2026
The iControl interface suffers from a critical missing secure attribute configuration in its cookie management logic, specifically regarding the HttpOnly and Secure flags on session-related cookies. This vulnerability arises when web applications fail to enforce strict security attributes for cookies that contain sensitive data, such as session identifiers or authentication tokens. In this specific instance, the application transmits these cookies over unencrypted HTTP connections without marking them with the Secure attribute, which restricts transmission to HTTPS channels only. Furthermore, if the HttpOnly flag is also absent or improperly configured, it allows client-side scripts running in the browser context to access and read cookie values directly via JavaScript APIs like document.cookie. This combination of missing attributes creates a significant exposure vector for attackers operating within the same network segment or those capable performing man-in-the-middle attacks against unencrypted traffic flows targeting the iControl management plane.
From an operational perspective, this flaw enables unauthorized extraction of sensitive information by malicious actors who can intercept network traffic passing through insecure channels. An attacker positioned between the client and the server on a public Wi-Fi network, a compromised router, or any intermediate node along the path to the unencrypted HTTP endpoint can capture these cookies using standard packet sniffing tools such as Wireshark or tcpdump. Once intercepted, the session identifiers contained within these cookies allow the attacker to hijack active user sessions without needing valid credentials. This leads directly to unauthorized access to the iControl interface, which typically provides administrative control over F5 BIG-IP systems and related infrastructure components. The ability to impersonate legitimate administrators poses a severe risk to system integrity, potentially allowing full compromise of network configurations, data exfiltration, or deployment of further malicious payloads within the protected environment.
This vulnerability aligns with CWE-614, which classifies as Sensitive Cookie in an HTTP Response Without Secure Attribute, and CWE-1004, which covers Sensitive Cookie Without HttpOnly Flag when applicable to client-side script access. In terms of offensive security frameworks, this flaw facilitates the MITM (Man-in-the-Middle) attack technique identified under ATT&CK Tactic TA0040 as Intercepting Traffic Capture or specifically leveraging Session Hijacking via cookie theft. The lack of encryption and proper attribute enforcement violates fundamental web application security principles outlined in OWASP guidelines for session management, particularly regarding the requirement to use secure flags and transport layer encryption for all sensitive cookies.
To mitigate this vulnerability, immediate remediation steps must focus on enforcing strict cookie attributes and securing communication channels. Administrators should configure the iControl interface to exclusively serve content over HTTPS using valid TLS certificates, thereby ensuring that all data in transit is encrypted at the application layer. Concurrently, developers or system administrators must update the web server configuration to include both the Secure and HttpOnly flags on all cookies containing session identifiers or other sensitive authentication data. The Secure flag ensures browsers only transmit these cookies over encrypted HTTPS connections, preventing interception via unencrypted HTTP requests. The HttpOnly flag prevents client-side scripts from accessing cookie values, thereby mitigating risks associated with Cross-Site Scripting (XSS) attacks that might attempt to steal sessions even if encryption is present. Additionally implementing Content Security Policy headers can provide an additional layer of defense by restricting script execution sources and further reducing the attack surface for potential session hijacking attempts.