Which SQL Injection Type Uses True/False Responses?
Short answer
D Blind SQL injection infers data from true/false responses when no error messages or query results are returned.
Question
Key Takeaways
The exam tests whether you can distinguish blind SQL injection from other SQLi families by the absence of error output and the use of boolean true/false inference; the trap is picking time-based simply because delay techniques are also blind.
Blind SQL injection is an inferential technique in which the attacker submits true/false SQL conditions and reads the application's behaviour instead of seeing query results or database errors. This page confirms option D and separates blind injection from union, error-based and time-based variants.
Common mistake: Many candidates choose time-based SQL injection because it also lacks visible output, but time-based relies on measured delays, whereas this scenario describes extracting data from true/false response differences.
Expert Analysis
Why the Answer Is Correct
Blind SQL injection matches the scenario exactly: the application returns no SQL error text and no query output, yet the attacker can submit boolean conditions and observe whether the page behaves as true or false. By chaining those inferred answers, the attacker reconstructs schema and data character by character. This is precisely the "no error message, infer from response" definition, so option D is the only fit. The unanimous learner votes for D are consistent with the CEHv12 objective on SQL injection types.
Why the Other Options Are Wrong
Union SQL injection (A) depends on appending a UNION SELECT and seeing the combined result set in the response, which the question explicitly rules out. Error-based injection (B) is defined by forcing database error messages that reveal structure, again contradicted by "does not show any error message." Time-based injection (C) infers data by measuring deliberate delays, not by true/false content differences; although it is a blind subtype, the described true/false response mechanism points to the broader blind category in D.
Community Comment Notes
As insaniunt noted, the attacker "doesn't directly see the results of the injected SQL query" and instead infers information from the application's response, which is the textbook blind model. shaody adds that "no data is transmitted through the web application" and the real result cannot be retrieved, reinforcing why union and error-based options fail. LordXander's terse "CEHv12 - 2225" reference and qwerty100's direct pick of D show the community consensus aligns with the exam blueprint, but the verdict rests on the wording of the scenario, not the vote count.
Official Reference
- https://owasp.org/www-community/attacks/Blind_SQL_Injection
- https://portswigger.net/web-security/sql-injection/blind
These links open the official vendor documentation in a new tab.
Exam Strategy
When a SQLi question says no error message and no visible query output, classify it as blind before looking at timing details. Time-based injection is a blind subtype, so choose it only when the stem explicitly mentions delays or response time.
Frequently Asked Questions
Why is time-based SQL injection not the best answer here?
How does blind SQL injection extract data with no output?
Community Votes
100% of anonymous learners picked answer D. Votes are pick records left by other test-takers — they are not the verified answer.
Discussion 4 contributions
Compiled from public community threads and reader submissions, lightly edited for clarity. Handles and vote tallies are shown as recorded, and comments reflect the views of individual contributors.
From public community threads 4
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insaniunt 👍 2 Answered DBlind SQL injection attacks, the attacker doesn't directly see the results of the injected SQL query but can infer information based on the application's response
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shaody 👍 1 Answered DNo data is transmitted through the web application, and it is not possible for an attacker to retrieve the actual result of the injection; therefore, it is called blind SQL injection.
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qwerty100 👍 2 Answered DD. Blind SQL injection
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LordXander 👍 2 Answered DCEHv12 - 2225
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