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[core] Potential ReDoS Vulnerability in init.js: Inefficient Regex May Cause Denial of Service #700

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14 changes: 9 additions & 5 deletions client/commonFramework/bindings.js
Original file line number Diff line number Diff line change
Expand Up @@ -21,6 +21,11 @@ window.common = (function(global) {
};

common.init.push(function($) {
function stripTrailingHashes(url) {
let i = url.length - 1;
while (i >= 0 && url[i] === '#') i--;
return url.slice(0, i + 1);
}

var $marginFix = $('.innerMarginFix');
$marginFix.css('min-height', $marginFix.height());
Expand Down Expand Up @@ -179,10 +184,9 @@ window.common = (function(global) {
});

$('#search-issue').on('click', function() {
var queryIssue = window.location.href
.toString()
.split('?')[0]
.replace(/(#*)$/, '');
var queryIssue = stripTrailingHashes(
window.location.href.toString().split('?')[0]
);
window.open(
'https://github.com/freecodecampchina/freecodecamp.cn/issues?q=' +
'is:issue is:all ' +
Expand All @@ -196,4 +200,4 @@ window.common = (function(global) {
});

return common;
}(window));
}(window));
4 changes: 2 additions & 2 deletions client/commonFramework/init.js
Original file line number Diff line number Diff line change
Expand Up @@ -46,13 +46,13 @@ window.common = (function(global) {
};

common.replaceFormActionAttr = function replaceFormAction(value) {
return value.replace(/<form[^>]*>/, function(val) {
return value.replace(/<form(?!<form)[^>]*>/, function(val) {
return val.replace(/action(\s*?)=/, 'fccfaa$1=');
});
};

common.replaceFccfaaAttr = function replaceFccfaaAttr(value) {
return value.replace(/<form[^>]*>/, function(val) {
return value.replace(/<form(?!<form)[^>]*>/, function(val) {
return val.replace(/fccfaa(\s*?)=/, 'action$1=');
});
};
Expand Down
3 changes: 2 additions & 1 deletion package.json
Original file line number Diff line number Diff line change
Expand Up @@ -21,7 +21,8 @@
"lint-json": "npm run lint-server && npm run lint-challenges && npm run lint-resources && npm run lint-utils",
"test-challenges": "babel-node seed/test-challenges.js | tap-spec",
"pretest": "npm run lint",
"test": "npm run test-challenges"
"test": "npm run test-challenges",
"test-redos": "mocha test/commonFramework/bindings.test.js"
},
"license": "(BSD-3-Clause AND CC-BY-SA-4.0)",
"dependencies": {
Expand Down
45 changes: 45 additions & 0 deletions test/commonFramework/bindings.test.js
Original file line number Diff line number Diff line change
@@ -0,0 +1,45 @@
// test/bindings.test.js
const { expect } = require('chai');
const { performance } = require('perf_hooks');

// 安全替代函数
function stripTrailingHashes(url) {
let i = url.length - 1;
while (i >= 0 && url[i] === '#') i--;
return url.slice(0, i + 1);
}

// 模拟原版逻辑(用于对比测试)
function originalReplace(url) {
return url.replace(/#+$/, '');
}

describe('✅ stripTrailingHashes replacement test', function () {
this.timeout(10000); // 最多允许10秒运行

it('should match behavior of original regex for normal cases', () => {
const cases = [
["https://a.com/page#", "https://a.com/page"],
["https://a.com/page###", "https://a.com/page"],
["https://a.com/page#section", "https://a.com/page#section"],
["https://a.com/page#section#", "https://a.com/page#section"],
["https://a.com/page", "https://a.com/page"],
];

for (const [input, expected] of cases) {
expect(stripTrailingHashes(input)).to.equal(expected);
expect(stripTrailingHashes(input)).to.equal(originalReplace(input));
}
});

it('should not hang on malicious long string input', () => {
const attack = '#'.repeat(100000) + '@';
const testUrl = 'https://a.com/' + attack;
const t0 = performance.now();
const result = stripTrailingHashes(testUrl);
const t1 = performance.now();
const duration = (t1 - t0) / 1000;
console.log(`⏱️ safeReplace() 执行耗时:${duration.toFixed(3)} s`);
expect(duration).to.be.lessThan(1); // 应该非常快(毫秒级)
});
});