F5 Big IP opens up vulnerability during configuration
.png)
F5 Networks’ popular load balancing software BIG-IP harbours a vulnerability that could let malicious code seep in using just an online form.
"Load balancing is an important web management process that keeps many internet services ticking," said F-Secure, which spotted the vulnerability. "Without it, banks, governments, and other organisations providing online services to large numbers of people would struggle to keep their websites running."
Senior security consultant Christoffer Jerkeby discovered the vulnerability during a routine assessment. More than 300,000 organisations including state bodies and large banks use BIG-IP, broadening the scope of potential damages.
"Further research found that, following a successful exploit, an adversary could turn the compromised device back against the organisation or even individuals using the affected services," it added.
F-Secure said it is yet to receive reports of misuse of this vulnerability.
"F5 is a popular technology and we found over 300,000 (potentially vulnerable) devices on-line. Google and services like Shodan can be used to search for these also. The F5 website also contains information on their clients and sectors," Dave Hartley, technical director at F-Secure, told SC Media UK.
He refrained from revealing the names of the vulnerable F5 clients, saying: "These companies may be at risk of compromise."
Curiously, BIG-IP itself is immune to the vulnerability. It creeps up only when an organisation mis-configures BIG-IP’s iRules, the procedures written in tool command language (Tcl) to direct incoming web traffic toward the correct web server.
"These iRules are created using the tool command language (Tcl). Certain coding practices that may seem perfectly functional and practical to an organisation can allow an attacker to inject arbitrary Tcl commands, which could be executed in the security context of the target Tcl script," the report said.
In some implementations of BIG-IP, injecting a malicious code can be as easy as filling an online form, F-Secure revealed.
The threat posed is way bigger than a simple data breach, Hartley told SC Media UK. "An attacker can leverage the issue to achieve much more than a data breach alone. If the prerequisites are met, it could result in an adversary taking full control of the F5."
However, the scope and depth of the attack will vary, depending on the objective of the attacker and the scale of operations of the target organisation, he said.
"The F5 is often used for perimeter security and traffic management and there have been issues identified in similar technologies in the past that have had a severe impact for some -- firewalls, anti-virus, e-mail sandbox technologies etc.," he explained.
Addressing the issue, F5 released a public advisory.
"This is not a vulnerability in Tcl, or F5 products, but rather an issue relating to coding practices used when writing Tcl code. As with most programming or scripting languages, it is possible to write code in a way that may create vulnerabilities. This is not something F5 can prevent the user from doing, as the issue does not lend itself to neither deterministic nor heuristic detection that covers all possible cases," it said.
"The Tcl documentation previously cited provides more comprehensive recommendations. However, the simple answer is that expressions in Tcl should always be braced," it added.
source scmagazineuk
Industry: Cyber Security

Latest Jobs
-
- IAM Consultant- OKTA
- Germany
- upto €90,000 plus benefits
-
I am looking for an experienced IAM process Manager to help drive forward a series of IAM implementation for a global Manufacturing business, Ideally you will be skilled with Okta and have knowledge of PAM Solutions, You will be responsible for: Driving the design and continuous improvement of complex IAM solutions in close collaboration with business partners Consult on the optimisation of IAM processes and design proper IT-based solutions to meet availability and quality targets Define technical specifications for SW-development (standards, design patterns, test cases, scenarios) and manage the life cycle of designed solutions Actively scan for relevant innovations and new technologies to identify further potential for improving IAM solutions and processes using OKTA Analyse new features of the regular Okta releases We are looking for someone with strong IAM experience as an Architect, Analyst, Technical Engineer, or similar role in the Identity and Security domain Experience with relevant certifications in development/administration, design and configuration of the Okta IAM platforms Familiar with LCM - joiners, movers, leavers, application federation - SAML, OIDC, SCIM and many other IAM terms Good mix of competences in IAM business process and project management concepts and tools e.g., ServiceNow, Jira, PRINCE2, SCRUM (agile)
-
- SAP Security Consultant
- France
- upto €70,000 plus benefits
-
I am looking for an experienced SAP Security Consultant. The ideal candidate will have a strong understanding of SAP security concepts and be able to apply them to real-world scenarios. ideally you will also have experience with Securitybridge or Onapsis, or a similar SAP security tool. Your responsibilities will include: Reviewing and auditing SAP security settings and controls Identifying and remediating security vulnerabilities Implementing security best practices Educating users on SAP security Experience experience in SAP security Experience with Securitybridge or Onapsis, or a similar SAP security tool would be very advantageous Strong understanding of SAP security concepts Excellent problem-solving and analytical skills Excellent communication and presentation skills Fluent in French & English
-
- Post Grad MSc Cyber security - Junior Cyber Risk Analyst wanted. UK
- United Kingdom
- Entry role
-
The perfect start to your new Cyber Security Career. Post Graduate Cyber Risk Analyst Wanted. Are you are fresh from earning your Cyber Security MSc and eager to start your career in Cyber Security? We are looking for a recent post graduate to join a forward thinking Cyber Security Consultancy for the ideal entry role into Cyber Security. Whilst employed industry experience is not expected, as full training and support will be provided, a history of recent education in Cyber Security / Cyber Risk is essential. We are looking for someone with an inquisitive mind, who is confident to ask the right questions and who isn't afraid to challenge the status quo. Superb communication skills are a must (in person, written and verbal) This is a UK based role that is remote first with monthly travel (1-2 a month) to meet with the team and in time to meet clients. If you aren’t available to travel this isn’t the opportunity. We are unable to provide VISA sponsorship as there will be a requirement to achieve Security clearance If you're adaptable, open to fresh perspectives, and excited to be part of a forward-thinking team and looking for an opportunity to help make a difference in a Cyber consulting role, this opportunity is for you. For more information apply here……
-
- Microsoft Exchange Contractor | London | OUTSIDE IR35 | SC Cleared
- London
- OUTSIDE IR35
-
Microsoft Exchange Contractor | London | OUTSIDE IR35 | SC Cleared • We require someone that has experience of migration exchange from windows server 2012 to 2019. • In depth understand of On-Prem exchange server management and deployment. • Experience migrating On-Prem exchange servers from 2012 upwards. • Secure Email Gateway experience essential Due to the nature of the requirement the individual must be commutable to London 2-3 days a week.