Hawk High

Summary

The giveReview function restricts each student to receiving a maximum of 5 reviews. However, the code does not increment the reviewCount after a review is submitted, making the restriction ineffective and allowing unlimited reviews.

Vulnerability Details

The relevant check:

require(reviewCount[_student] < 5, "Student review count exceeded!!!");

is supposed to limit a student to 5 reviews. However, reviewCount[_student] is never updated in the function. As a result, the condition always passes if the initial value is 0, and the function can be called repeatedly without restriction.

Missing logic:

reviewCount[_student] += 1;

This oversight completely bypasses the intended limitation and weakens the review system.

Impact

• Logic flaw: The intended 5-review cap is meaningless and never enforced.

• Student abuse: A teacher could repeatedly review (and penalize) the same student, especially with bad reviews.

• Score manipulation: A malicious teacher can reduce a student’s score significantly beyond intended design.

Tools Used

Manual code inspection and logic tracing.

Recommendations

Increment the review count after a review is submitted:

reviewCount[_student] += 1;