CVE-2026-31865 (GCVE-0-2026-31865)

Vulnerability from cvelistv5 – Published: 2026-03-18 02:50 – Updated: 2026-03-18 18:39
VLAI
Title
Elysia Cookie Value Prototype Pollution
Summary
Elysia is a Typescript framework for request validation, type inference, OpenAPI documentation, and client-server communication. Prior to version 1.4.27, an Elysia cookie can be overridden by prototype pollution , eg. `__proto__`. This issue is patched in 1.4.27. As a workaround, use t.Cookie validation to enforce validation value and/or prevent iterable over cookie if possible.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-18 18:36 UTC
CWE
  • CWE-1321 - Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7886 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
elysiajs elysia Affected: < 1.4.27
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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