CVE-2026-31865
Elysia Cookie Value Prototype Pollution
6.5
MEDIUM
CVSS 3.1
EPSS 0.02%
Description
### Impact Elysia cookie can be overridden by prototype pollution , eg. `__proto__` Sending cookie with the follows name can override cookie value: ```bash __proto__=%7B%22injected%22%3A%22polluted%22%7D ``` ### Patches Patched by 1.4.27 ### Workarounds 1. Use t.Cookie validation to enforce validation value 2. Prevent iterable over cookie if possible
How to fix CVE-2026-31865
To remediate CVE-2026-31865, upgrade the affected package to a fixed version below.
- —upgrade to 1.4.27 or later
Is CVE-2026-31865 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 1.4.27
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |