# What is CVE-2016-9244? > CVE-2016-9244 is a high-severity flaw (CVSS 7.5) in Big-IP Local Traffic Manager from F5, published on 9 February 2017. It is not on the list of flaws known to be exploited today. The latest forecast puts its chance of use in the next 30 days at 74%. If you run an affected version, plan in the vendor’s fix. Canonical page: https://www.precursorintelligence.com/what-is/cve-2016-9244 ## At a glance - **Verdict:** Fix this soon. Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month. - **Precursor Intelligence risk score:** 62 out of 100 (Medium); action: Plan remediation. Kept up to date as the evidence changes. - **Severity:** High (CVSS 7.5 out of 10) - **Known to be exploited:** No, not on the list of flaws known to be exploited today - **Chance of use in the next 30 days:** 74% (latest exploit-likelihood forecast) - **Published:** 9 February 2017 - **Record last updated:** 20 April 2025 - **Main product:** Big-IP Local Traffic Manager from F5 - **Affected products:** 10 ## What is CVE-2016-9244? In plain terms It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can read data. ### The official description A BIG-IP virtual server configured with a Client SSL profile that has the non-default Session Tickets option enabled may leak up to 31 bytes of uninitialized memory. A remote attacker may exploit this vulnerability to obtain Secure Sockets Layer (SSL) session IDs from other sessions. It is possible that other data from uninitialized memory may be returned as well. ### What kind of flaw is it? - CWE-200: Exposure of Sensitive Information to an Unauthorized Actor ### How an attack on it works - Where an attacker can be: Anywhere on the internet - How hard it is to pull off: Easy: no special conditions - Login needed first: No login needed - Does someone have to click: No, nobody has to do anything - What an attacker gets: Can read data Severity vector: `CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N` ## Is CVE-2016-9244 being exploited? Not that we know of It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 74%. That can change at any time, which is why we keep watching. Exploit likelihood over the last 7 days: 74%, 74%, 74%, 74%, 74%, 74%, 74%. ### Timeline - 9 February 2017: Published - 20 April 2025: Record last updated - 5 August 2025: Exploit likelihood jumped - 2 September 2025: Exploit likelihood fell ### How Precursor Intelligence ranks it CVE-2016-9244 scores **62 out of 100 (Medium)**, with the action "Plan remediation". Every published flaw gets a risk score from 0 to 100, kept up to date as the evidence changes. Four things go into the score, from the one that counts most to the ones that count less: - Evidence it is being exploited: biggest factor - How severe it is: strong factor - How widely exposed it is: smaller factor - Threat activity around it: smaller factor 85 and above is Critical. Anything confirmed as exploited is always marked for an emergency patch, whatever its score. When this flaw matches software you track, it lands in your list with its score and the reasons behind it. ## Who is affected by CVE-2016-9244? The published record lists 10 products. - [Big-IP Local Traffic Manager](https://www.precursorintelligence.com/product/f5/big-ip_local_traffic_manager) by [F5](https://www.precursorintelligence.com/vendors/f5) (Application): 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.6.0, 11.6.1, 12.0.0, 12.1.0, 12.1.1, 12.1.2 - [Big-IP Access Policy Manager](https://www.precursorintelligence.com/product/f5/big-ip_access_policy_manager) by [F5](https://www.precursorintelligence.com/vendors/f5) (Application): 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.6.0, 11.6.1, 12.0.0, 12.1.0, 12.1.1, 12.1.2 - [Big-IP Advanced Firewall Manager](https://www.precursorintelligence.com/product/f5/big-ip_advanced_firewall_manager) by [F5](https://www.precursorintelligence.com/vendors/f5) (Application): 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.6.0, 11.6.1, 12.0.0, 12.1.0, 12.1.1, 12.1.2 - [Big-IP Analytics](https://www.precursorintelligence.com/product/f5/big-ip_analytics) by [F5](https://www.precursorintelligence.com/vendors/f5) (Application): 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.6.0, 11.6.1, 12.0.0, 12.1.0, 12.1.1, 12.1.2 - [Big-IP Application Acceleration Manager](https://www.precursorintelligence.com/product/f5/big-ip_application_acceleration_manager) by [F5](https://www.precursorintelligence.com/vendors/f5) (Application): 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.6.0, 11.6.1, 12.0.0, 12.1.0, 12.1.1, 12.1.2 - [Big-IP Application Security Manager](https://www.precursorintelligence.com/product/f5/big-ip_application_security_manager) by [F5](https://www.precursorintelligence.com/vendors/f5) (Application): 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.6.0, 11.6.1, 12.0.0, 12.1.0, 12.1.1, 12.1.2 - [Big-IP Link Controller](https://www.precursorintelligence.com/product/f5/big-ip_link_controller) by [F5](https://www.precursorintelligence.com/vendors/f5) (Application): 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.6.0, 11.6.1, 12.0.0, 12.1.0, 12.1.1, 12.1.2 - [Big-IP Policy Enforcement Manager](https://www.precursorintelligence.com/product/f5/big-ip_policy_enforcement_manager) by [F5](https://www.precursorintelligence.com/vendors/f5) (Application): 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.6.0, 11.6.1, 12.0.0, 12.1.0, 12.1.1, 12.1.2 - [Big-IP Global Traffic Manager](https://www.precursorintelligence.com/product/f5/big-ip_global_traffic_manager) by [F5](https://www.precursorintelligence.com/vendors/f5) (Application): 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.6.0, 11.6.1 - [Big-IP Protocol Security Module](https://www.precursorintelligence.com/product/f5/big-ip_protocol_security_module) by [F5](https://www.precursorintelligence.com/vendors/f5) (Application): 11.4.0, 11.4.1 ## How do I fix CVE-2016-9244? 1. **Check whether you run it.** Compare your versions with the affected products above. Not sure what you run? Precursor Intelligence can work it out from your public website, or you can pick it from a list. 2. **Apply the vendor’s fix.** Install the update named in the vendor’s advisory. We’ve put the advisory first in the list. 3. **If you can’t patch today.** Follow any mitigation the vendor publishes, and limit who can reach the affected system from the internet until the update is in. 4. **Keep an eye on it.** Track the product and we tell you as soon as we spot this flaw on the list of exploited flaws, or a jump in its exploit likelihood. ### References - [support.f5.com](https://support.f5.com/csp/article/K05121675) (Mitigation, Vendor advisory) - [packetstormsecurity.com](http://packetstormsecurity.com/files/141017/Ticketbleed-F5-TLS-Information-Disclosure.html) - [securityfocus.com](http://www.securityfocus.com/bid/96143) - [securitytracker.com](http://www.securitytracker.com/id/1037800) (Third-party advisory, Vulnerability database) - [blog.filippo.io](https://blog.filippo.io/finding-ticketbleed/) - [filippo.io](https://filippo.io/Ticketbleed/) - [github.com](https://github.com/0x00string/oldays/blob/master/CVE-2016-9244.py) - [exploit-db.com](https://www.exploit-db.com/exploits/41298/) ## Questions ### What is CVE-2016-9244? CVE-2016-9244 is a high-severity flaw in Big-IP Local Traffic Manager from F5, published on 9 February 2017. It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can read data. ### How serious is CVE-2016-9244? It scores 7.5 out of 10 on the CVSS severity scale, which is high. Our risk score for CVE-2016-9244 is 62 out of 100, which is Medium. Its action is "Plan remediation". Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month. ### Is CVE-2016-9244 being exploited? It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 74%. That can change at any time, which is why we keep watching. ### Which versions does CVE-2016-9244 affect? For Big-IP Local Traffic Manager from F5: 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3 and 7 more. The record lists 10 products in all, each with its versions, under "Who is affected" on this page. ### How do I fix CVE-2016-9244? Install the update the vendor names in its advisory, linked first under "How do I fix" on this page. If you can't patch today, follow the vendor's mitigation and limit who can reach the affected system from the internet. ## Does CVE-2016-9244 affect you? Precursor Intelligence keeps checking for you: - **Tell us what you run.** Pick your software from a list, or let us work it out from your website. - **We match it to every flaw.** Over 400,000 published flaws, checked against your list. - **Ranked by real-world risk.** Every flaw gets a 0 to 100 risk score, kept up to date, led by evidence criminals are using it. - **Told as soon as we know.** An alert by email, in the app or by webhook to your own tools. Start free (no card, nothing to install): https://www.precursorintelligence.com/register Book a demo: https://www.precursorintelligence.com/contact