Lead Security Engineer - Vulnerability Response (Imunify360)

CloudLinux Inc.; Madrid; Remote; EUR 90,000 - 120,000; Full time

Benefits offered by this job

Fully remote work

Flexible hours

Paid vacation 24 days/year

10 national holidays included

Unlimited sick leave

Private medical insurance

Co-working and gym reimbursement

Education budget

Job summary

CloudLinux Inc. is seeking a Lead Security Engineer - Vulnerability Response to own and extend the vulnerability response pipeline end to end.

You will combine deep web application security expertise with strong automation, leading a small team of security analysts and collaborating with automation, QA, and marketing. You will design AI-driven processes, write and review ModSecurity/Coraza rules, and drive time-to-protection metrics while maintaining system stability on shared hosting

Qualifications

• 5+ years in web/application security including vulnerability research and WAF engineering.
• Deep understanding of web attack classes and detection in HTTP traffic.
• Hands-on experience writing WAF rules and regex patterns.
• Strong Python for automation pipelines in production.
• Upper-intermediate English or better.

Responsibilities

• Design and build AI-driven vulnerability response pipeline from disclosure to advisory.
• Extend WordPress-plugin pipeline to ModSecurity/Coraza rules.
• Write and review WAF rules for real-world vulnerabilities.
• Build test harnesses to validate rules against exploits and traffic.
• Lead and mentor security analysts and coordinate with automation/QA/marketing.
• Define and track time-to-protection, coverage, and false positives.
• Automate advisory generation with marketing review flow.

Skills

Web security

WAF rules

Python automation

PHP code reading

AI/LLM tooling

Leadership

Product mindset

English proficiency

Threat/attack knowledge

Tools

ModSecurity/SecLang

OWASP CRS

Regular expressions

Coraza

Job description

We are looking for a Lead Security Engineer - Vulnerability Response to join our Web Protection Team.

CloudLinux is a global remote-first company. We are driven by our principles: do the right thing, employees first, we are remote first, and we deliver high-volume, low-cost Linux infrastructure and security products that help companies to increase the efficiency of their operations. Every person on our team supports each other and does what we can to ensure we all are successful.

Check out our website for more information: cloudlinux.com

Imunify360 Security Suite is an innovative security solution designed specifically for shared and VPS/Dedicated servers. The automated, easy-to-use solution with the six-layer approach to security delivers comprehensive and complete attack prevention.

The challenge ahead

When a critical vulnerability in a popular web application or WordPress plugin goes public, attackers start exploiting it within hours. Most site owners can't patch that fast. We want our customers protected before the first attack reaches them, and we want them to know it.

That's the challenge we're hiring for:

• AI-driven vulnerability response. Build and run a pipeline that detects new high and critical vulnerabilities, generates WAF rules with AI assistance, validates them, and ships them to production in a short window
• Protection plus public announcement, both automated. The same pipeline that ships the rule also produces the public advisory. Every critical vulnerability we cover is announced soon after the rule ships, so customers and the market see that Imunify closed it first
• Build on what works. An AI-assisted pipeline already runs for our WordPress protection plugin. The first big project is to extend this approach to ModSecurity/Coraza WAF rules
• Speed without breaking sites. On shared hosting, a rule that blocks legitimate traffic is a customer incident. Fast and precise both matter
• Make it measurable. Time-to-protection, coverage of critical vulnerabilities, and false-positive rate are the numbers this role owns

About The Role

You will own the vulnerability response pipeline end to end and be its main builder. You combine deep web application security expertise with strong automation skills, and you think about the product: what customers need, what to measure, what to build next. You'll lead a small team of security analysts and work closely with automation, QA, and marketing.

What You'll Do

• Design and build the AI-driven pipeline from disclosure to announcement: vulnerability intake, triage, rule drafting, testing, release, and the public advisory
• Lead the extension of our existing WordPress-plugin pipeline to ModSecurity/Coraza rules
• Write and review WAF rules (ModSecurity/SecLang) for real-world web vulnerabilities
• Build test harnesses that check rules against exploits and real traffic before release
• Lead and mentor security analysts: set priorities, review their work, remove blockers
• Define and track time-to-protection, coverage, and false-positive rate, and improve them
• Automate advisory generation as part of the pipeline, and agree the format and review flow with marketing

Requirements

What we're looking for:

• 5+ years in web/application security: vulnerability research, detection engineering, WAF engineering, or similar
• Deep understanding of web attack classes (SQLi, XSS, RCE, auth bypass, path traversal, file upload, deserialization) and how to detect them in HTTP traffic
• Hands-on experience writing WAF rules (ModSecurity/SecLang, OWASP CRS, or similar) and regular expressions
• Able to read PHP code and understand a vulnerability from an advisory or a patch diff
• Strong Python: you've built automation pipelines that run in production. CI/CD and automated testing
• Hands-on daily use of AI/LLM tools; you know where to trust them and how to verify their output
• Proven track record of leading a technical project end to end
• Product mindset: you reason about customer impact, not only technical correctness
• Upper-intermediate English or better

Nice to have:

• WordPress ecosystem security: plugin vulnerabilities, vulnerability feeds (Wordfence, Patchstack, WPScan), CVE credits or bug bounty
• Coraza or other WAF engines
• Exploit analysis or threat intelligence background
• Linux server administration, hosting industry

Personal skills:

• Strong ownership: you take a goal, not a task list
• See the whole process and find the bottleneck, not only fix individual issues
• Communicate clearly and raise risks early
• Calm under pressure: critical vulnerabilities don't wait for working hours
• Comfortable making decisions with incomplete information

Benefits

What's in it for you?

• A focus on professional development
• Interesting and challenging projects
• Fully remote work with flexible working hours, that allows you to schedule your day and work from any location worldwide
• Paid 24 days of vacation per year, 10 days of national holidays, and unlimited sick leaves
• Compensation for private medical insurance
• Co-working and gym/sports reimbursement
• Budget for education
• The opportunity to receive a reward for the most innovative idea that the company can patent

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