Submission Details
Severity:
[H-1] No increase reviews count will make the check always true, meaning that more than five reviews can be given
Summary
In LevelOne::giveReview the protocol checks whether the reviews given are lower than 5. However, this will always be true because the variable storing a given student review is not incremented (reviewCount[_student]). This can lead to multiple reviews being given and a malicious user can continue to lower the student's grade.
Impact
Teacher can give more than 5 reviews
Tools Used
Manual review
Proof of Code: Add this test and run it.
function test_confirm_can_give_review_more_than_4_times() public schoolInSession {
for (uint i = 0; i < 6; i++) {
vm.warp(block.timestamp + 1 weeks);
vm.prank(alice);
levelOneProxy.giveReview(harriet, false);
}
console2.log('Harriet scrore: ', levelOneProxy.studentScore(harriet));
assert(levelOneProxy.studentScore(harriet) == 40);
}
Recommendations: Increase student's review count everytime when a review is given.
function giveReview(address _student, bool review) public onlyTeacher {
if (!isStudent[_student]) {
revert HH__StudentDoesNotExist();
}
require(reviewCount[_student] < 5, "Student review count exceeded!!!");
require(block.timestamp >= lastReviewTime[_student] + reviewTime, "Reviews can only be given once per week");
// where `false` is a bad review and true is a good review
if (!review) {
studentScore[_student] -= 10;
}
// Update last review time
+ reviewCount[_student]++;
lastReviewTime[_student] = block.timestamp;
emit ReviewGiven(_student, review, studentScore[_student]);
}
Updates
Lead Judging Commences
yeahchibyke 6 months ago
Submission Judgement Published Assigned finding tags:
reviewCount not updated
`reviewCount` for students is not updated after each review session
Rewards breakdown
nSLOC
243This contest has a flat reward structure with the following payouts:
100 EXP
20 EXP
2 EXP
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