CVE WatchJul 9, 2026

CVE-2021-42237

Sitecore XP Remote Command Execution Vulnerability

CVSS

9.8

Critical

EPSS

97.9%

p100

KEV

YES

Mar 25, 2022

Exploit Today

0-100

Published: Nov 5, 2021 · Last modified: Jul 9, 2026 · CWE-502

EPSS · 30d

97.9%EPSS · 30 days99.2%

2026-06-302026-07-16

KEV catalog record

Product

Sitecore / XP

Vulnerability

Sitecore XP Remote Command Execution Vulnerability

Added to KEV

Mar 25, 2022

Remediate by

Apr 15, 2022

Known ransomware use

Yes

Summary description

Sitcore XP contains an insecure deserialization vulnerability which can allow for remote code execution.

Required action

Apply updates per vendor instructions.

Notes

https://nvd.nist.gov/vuln/detail/CVE-2021-42237

Technical description

Sitecore XP 7.5 Initial Release to Sitecore XP 8.2 Update-7 is vulnerable to an insecure deserialization attack where it is possible to achieve remote command execution on the machine. No authentication or special configuration is required to exploit this vulnerability.

Official references

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