SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-44483

Because field names in submitted form data are passed directly to setPath via preprocessFormData (and through parseFormData / validate), an attacker who can submit a form to a Remix / React Router app using the library can set arbitrary properties on…

HIGH 8.2EPSS 0.31%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.31%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

RVF (formerly Remix Validated Form) provides easy form validation and state management for React. From 6.0.0 to before 6.0.4 and 7.0.2, setPath in @rvf/set-get (used by @rvf/core to flatten incoming form data into a nested object) does not block the keys __proto__, constructor, or prototype when walking a path. Because field names in submitted form data are passed directly to setPath via preprocessFormData (and through parseFormData / validate), an attacker who can submit a form to a Remix / React Router app using the library can set arbitrary properties on Object.prototype of the running server process. This is a default-reachable prototype pollution primitive: no special configuration is required. Any endpoint that accepts a form via parseFormData or runs a validator created with createValidator is affected. This vulnerability is fixed in 6.0.4 and 7.0.2.

CVSS 3.1
8.2 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L
EPSS
0.31% probability · 23th percentile
CISA KEV
Not listed
Weakness
CWE-1321
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.