CVE-2026-104848 Tinypool: Prototype Pollution gadget in worker options leads to Remote Code Execution
Prototype pollution in Tinypool allows attackers to inject code into worker threads via execArgv or env, leading to remote code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-104848?
CVE-2026-104848 is a critical code injection vulnerability in tinylibs tinypool, published on 2 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Tinypool is a minimal Node.js worker thread pool implementation. Prior to 2.1.1, Tinypool constructs ThreadPool.options from a normal options object and reads the execArgv and env worker options in dist/index.js, allowing values inherited from a polluted Object.prototype to be copied into own properties and passed to worker_threads.Worker. An attacker who can first pollute either property can cause each newly spawned worker to load attacker-selected JavaScript through command-line preload arguments or NODE_OPTIONS, resulting in code execution with the host process's privileges and possible access to CI secrets, signing material, or build artifacts. This issue is fixed in version 2.1.1.
Weakness: CWE-1321
Which versions are affected by CVE-2026-104848?
2 open source packages ship an affected version, including tinypool.
| Package | Affected | Fixed in |
|---|---|---|
tinypool npm | All versions | 2.1.1 |
tinypool npm | All versions | 2.1.1 |
How do I fix CVE-2026-104848?
Upgrade tinypool to 2.1.1 or later.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-104848 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-104848 exists.
Sources
Also known as GHSA-5gmw-xhrv-c9v3, MINI-395r-8rr8-28vv, MINI-6ppf-979g-65jp, MINI-9cc7-f84v-rp8w, MINI-mx77-52gw-3qqg, ROOT-APP-NPM-CVE-2026-104848.