Not all bugs are so simple to find. Some remain concealed and patiently wait for a suitable time for causing harm. It is at this point that manual software testing services for software come into play.
While automated tools are fast and powerful, they can overlook the small details that come easily to the human observer. Manual testers can walk in the shoes of real users, or even malicious users, to identify vulnerabilities that automated tools might overlook.
Research has shown that 35% of the most serious bugs are discovered either manually or using human analysis. We will discuss in this article the role of intuition, creativity, or intelligent testing, what they accomplish, and the reasons why they consider manual testing essential for software security.
Automation follows rules. Humans question them—and that’s the key difference. With manual QA testing, testers can freely explore an application, trying unexpected user paths and logic flows that automated scripts simply don’t anticipate. Instead of checking only “happy paths,” they actively look for what could go wrong. Manual testers rely on:
This approach is especially effective at uncovering: Negative testing scenarios (What happens when users make mistakes?) UI security issues like exposed admin buttons Weak input validation that allows bad data to slip through
Automation confirms that features work. Manual testing explains how and why they might fail.
Manual security testing mirrors the way real attackers think. Instead of running blind scans, testers actively interact with the system—clicking, modifying requests, and intentionally breaking things. Common issues uncovered through manual testing include:
Here’s a simple real-world example: A tester manually changes a request parameter that controls user roles. No warning appears. Suddenly, a regular user gains admin access. That’s a serious privilege escalation flaw—found only because a human decided to “try something different.” According to IBM’s Cost of a Data Breach report, fixing vulnerabilities after release can cost up to 15 times more than fixing them before launch. Manual testing helps teams catch these expensive mistakes early.
Some bugs don’t show up in clean, controlled environments. They appear in messy, real-life situations—and that’s where manual testing shines. Testers often uncover issues during: Manual code review when business logic feels off Patch verification to ensure fixes don’t create new problems Token validation checks after login and authentication flows They also simulate real pressure through: Concurrency testing, where many users act at the same time Session timeout testing to prevent session hijacking Automated tools may pass these checks, but humans notice subtle warning signs—like sessions that never expire or users staying logged in longer than they should.
Manual testing acts as the final safety net before launch. During pre-release validation, testers perform manual smoke testing to confirm that critical features still work securely.
This stage includes:
Manual testing is also ideal for last-minute changes. Testers can quickly verify fixes without rewriting automation scripts, ensuring nothing new breaks at the final hour.
Effective software vulnerability testing is never just manual or automated—it’s a smart mix of both. Automation provides speed and coverage, while manual testing delivers depth and insight. Manual testers support broader strategies by:
Teams that use this combined approach report up to 27% fewer post-release security incidents, according to industry surveys.
You can automate speed, but you can’t automate human insight. Manual QA testing provides security testing with curiosity, creativity, and context. Testers identify patterns, prove assumptions, and reveal logical flaws that automated testing cannot. If the security plan involves just automation, then some risks may be lurking in the background that haven't been caught yet by automation solutions. It may be worth reflecting on the testing process and ask yourself: Do we have enough human eyes on this software? It’s often people rather than code that can spot the biggest risks or potential problems in software.
Q: Does manual testing still matter in a DevOps environment?
Yes. It’s essential for exploratory testing, edge cases, and security validation.
Q: What security issues can manual testers find?
Everything from form tampering and token validation issues to privilege escalation and logic flaws that automation often misses.