Web application security Engineer

About the role

You will create and validate the detection content that protects our customers: IDPS signatures, application control rules, and DLP rules. This is a hands-on role in our security lab, where you will generate real attack traffic, research vulnerabilities and applications, and make sure every rule is accurate, effective, and ready for production.

What you'll do

Write security rules

• Write IDPS signatures for exploits, malware, command-and-control traffic, and network attacks, with the right severity, action (alert / block / reject), and protocol scope
• Build application control rules to identify and control social media, streaming, file sharing, remote access, unsanctioned SaaS, and AI tools
• Create DLP rules to detect sensitive data (personal and financial data, confidential documents, source code) across web, email, and file transfer channels

Test and validate

• Set up test scenarios in our lab and generate traffic using browsers, command-line tools, packet captures, and safe proof-of-concept exploits
• Confirm that each rule triggers and that logs show the correct rule, severity, action, and source
• Test against normal everyday traffic to find and fix false positives before rules ship
• Build and maintain a repeatable test set so rules keep working after product updates

Research and document

• Track new CVEs, exploit techniques, and emerging applications, and turn them into working detections
• Study public r
• Study public rulesets to learn coverage patterns and find gaps in our own
• Write a short validation note for each batch: what it detects, how it was tested, and what it doesn't cover

What we're looking for

• 2-5 years of hands-on experience writing detection rules or signatures with Snort, Suricata, Zeek, YARA, Sigma, or similar
• Strong networking fundamentals: TCP/IP, HTTP/HTTPS, DNS, TLS, and packet analysis with Wireshark or pcap tools
• Experience testing rules with PoC exploits and tuning them to reduce false positives
• Exposure to CVE and vulnerability research, with the ability to read advisories and turn them into detections
• Working knowledge of Python or Bash for test automation, and comfort with Linux
• Clear written communication, since you'll document what each rule covers and what it doesn't

Good to have

• Experience with deep packet inspection, application identification (nDPI or similar), or DLP regex and pattern work
• Background at a network security vendor (firewall, IPS, NGFW, secure web gateway)
• Public work such as GitHub rules, blog posts, CVE credits, or CTF participation

This role is not

A SOC monitoring, alert triage, or pure penetration testing role. We are looking for people who write and test detection rules.

A BIT ABOUT US

Appknox is one of the top Mobile Application security companies recognized by Gartner and G2. A profitable B2B SaaS startup headquartered in Singapore & working from Bengaluru.

The primary goal of Appknox is to help businesses and mobile developers secure their mobile applications with a focus on delivery speed and high-quality security audits.

Appknox has helped secure mobile apps at Fortune 500 companies with major brands spread across regions like India, South-East Asia, Middle-East, US, and expanding rapidly. We have secured 300+ Enterprises globally.

We are a 65+ incredibly passionate team working to make an impact and helping some of the biggest companies globally. We work in a highly collaborative, very fast-paced work environment. If you have what it takes to be part of the team, we are excited and let’s speak further.

The Opportunity

To join the security team engaging with multiple clients, helping them with end to end security audits, also research about new topics and vulnerabilities to be added to the scanner, present it in conferences.

What An Ideal Candidate Would Look Like: 

• Skills - Application Penetration Testing (Web, iOS and Android), experience with IoT testing, source code audits.
• Technology Stack: AWS, GCP, Objective C, Java, Python
• Responsibilities: Engage with clients for scoping call, perform security audits, remediation call with clients to patch the issues, research on new technologies/vulnerabilities

Minimum Requirements

• 2-4+ years of experience in application security and vulnerability research
• Strong foundation in mobile app security - Android or Ios
• Proven track record of discovering and disclosing CVEs in mobile platforms or popular applications (provide - github/bug bounty profiles)
• Strong understanding of exploit mitigations and proven ability to bypass them
• Should be able to architect automated detection logic for new vulnerabilities and integrate them into our security products
• Develop AI-driven agents to automate dynamic analysis
• Should be able to Leverage AI/LLMs to augment Pentesting efforts
• Ability to work independently in a fast-paced environment, balancing deep research with practical deliverables

Good to have Requirements

• Understanding of AI/ML security risks

Responsibilities

• Security assessment of web/mobile applications on various platforms
• Focusing on Mobile Application Security Research for new vulnerabilities
• Static and Dynamic Code Analysis
• Develop and interpret security standards and guides
• Automation of exploit development 
• Understand and explain the results with impact on business and compliance status
• Continuously learning and training on latest tools and technique

Work Expectations

Within 1 month

Training on processes, security workflows and develop understanding on internal tools.

Within 3 months

Actively contributing in exploit development and automation of it with the team.

Within 6 months

Expected to achieve Subject Matter Expert status on our core security products. We expect you to validate your findings against real-world conditions, with a strong emphasis on translating internal discoveries into actionable bug bounty submissions and earned CVEs to benchmark your impact against the external security community.

Within 1 Year

By the end of your first year, you will be expected to produce and submit a piece of novel, peer-reviewed security research. This deliverable must be of a quality suitable for top-tier industry conferences.

Personality traits we really admire

• A confident and dynamic working persona, which can bring fun to the team, and a sense of humour, is an added advantage.
• Great attitude to ask questions, learn and suggest process improvements.
• Has attention to details and helps identify edge cases.
• Highly motivated and coming up with fresh ideas and perspectives to help us move towards our goals faster.
• Follow timelines and absolute commitment to deadlines.

Interview Process - would be team specific

• Round 1- CTF round 
• Round 2 -Profile Evaluation; HR
• Round 3 -Technical Interview with security team members
• Round 4 -Technical Interview with the Hiring Manager
• Round 5 -Technical round with CTO
• Round 6 -HR Round

Compensation

• As per Industry Standards

Why Join Us

• Freedom & Responsibility: If you are a person who enjoys challenging work & pushing your boundaries, then this is the right place for you. We appreciate new ideas & ownership as well as flexibility with working hours.
• Great Salary & Equity: We keep up with the market standards & provide pay packages considering updated standards. Also as Appknox continues to grow, you’ll have a great opportunity to earn more & grow with us. Moreover, we also provide equity options for our top performers.
• Holistic Growth: We foster a culture of continuous learning and take a much more holistic approach to train and develop our assets: the employees. We shall also support you all on that journey of yours.
• Transparency: Being a part of a start-up is an amazing experience, one of the reasons being open communication & transparency at multiple levels. Working with Appknox will give you the opportunity to experience it all first-hand.