CRITICAL

CVE-2021-42136

CVSS v3

CRITICAL

EPSS Score

4.7 %

exploit probability, as of 2026-10-19

CISA KEV

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Neither OSV.dev nor the vendor advisories we read list affected versions for CVE-2021-42136 yet.

Full record on NVD

Description

A stored Cross-Site Scripting (XSS) vulnerability in the Missing Data Codes functionality of REDCap before 11.4.0 allows remote attackers to execute JavaScript code in the client's browser by storing said code as a Missing Data Code value. This can then be leveraged to execute a Cross-Site Request Forgery attack to escalate privileges to administrator.

Technical details

Published: 2022-04-13
Exploit-DB: EDB-50877

Frequently asked questions

What is CVE-2021-42136?

Is CVE-2021-42136 actively exploited?

Active exploitation of CVE-2021-42136 has not been confirmed. Its EPSS score was 4.7% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-42136?

CVE-2021-42136 has a CVSS v3 base score of 9 (CRITICAL severity).

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