Prototype Pollution Vulnerability in Elysia Framework by Elysia JS

CVE-2026-31865

What is CVE-2026-31865?

The Elysia framework, a popular Typescript tool for request validation and client-server communication, is susceptible to a prototype pollution issue that allows an Elysia cookie to be unintentionally overridden. This vulnerability arises when malicious inputs alter the prototype of an object, impacting the integrity of cookies processed by the framework. Users are encouraged to update to version 1.4.27 or higher, where the issue has been patched. Alternatively, employing t.Cookie validation can mitigate risks by enforcing stringent validation of cookie values and preventing iteration over cookies when applicable.

Human OS v1.0:
Ageing Is an Unpatched Zero-Day Vulnerability.

Remediate biological technical debt. Prime Ageing uses 95% high-purity SIRT6 activation to maintain genomic integrity and bolster systemic resilience.

Deploy the Patch →

References