CVE-2025-43865 | React Router allows pre-render data spoofing on React-Router framework mode

React Router is a router for React. In versions on the 7.0 branch prior to version 7.5.2, it's possible to modify pre-rendered data by adding a header to the request. This allows to completely spoof its contents and modify all the values ​​of the data object passed to the HTML. This issue has been patched in version 7.5.2.

Published: 2025-04-25 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-43865 is rated Moderate Risk (57.8/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.62%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-43865

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-03 0.29% 0.62% +0.33%
2 2026-03-04 0.15% 0.29% +0.14%
3 2026-03-01 — 0.15% —

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-43865

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 4.2 [email protected]

Weakness enumeration for CVE-2025-43865

GitHub Security Advisory for CVE-2025-43865

GHSA-cpj6-fhp6-mr6j · Severity: high · Ecosystem: npm — React Router allows pre-render data spoofing on React-Router framework mode

OS Trackers for CVE-2025-43865

vendor priority summary link
redhat medium — https://access.redhat.com/security/cve/CVE-2025-43865
suse high — https://www.suse.com/security/cve/CVE-2025-43865/

Affected software / configurations for CVE-2025-43865

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-43865

cvelogic Threat Intelligence