CVE-2021-42237
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…
Browse: All 2021 CVEs · All vendors
- CVSS score
- 9.8 Critical
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- CISA KEV
- Yes — actively exploited (added 2022-03-25, remediation due 2022-04-15)
- Ransomware
- Known ransomware campaign use
- Weakness (CWE)
- CWE-502
- Published
- 2021-11-05
- Last modified
- 2026-07-09
- NVD status
- Analyzed
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.
Affected products
- sitecore experience platform
Affected ranges per NVD CPE data; confirm exact versions in the vendor advisory.
Required action (CISA)
Apply updates per vendor instructions. Federal remediation deadline: 2022-04-15.
How to prioritize this
This vulnerability is on the CISA KEV list, meaning it is being actively exploited — treat it as urgent regardless of the raw CVSS number. Use the live CVE lookup for the latest NVD data, and the CVSS 3.1 calculator to model your own environmental score. For the actively exploited vulnerabilities that matter this week, read The Exploit HQ daily security brief.
References
- http://packetstormsecurity.com/files/164988/Sitecore-Experience-Platform-XP-Remote-Code-Execution.html
- https://blog.assetnote.io/2021/11/02/sitecore-rce/
- https://support.sitecore.com/kb?id=kb_article_view&sysparm_article=KB1000776
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-42237
FAQ
Is CVE-2021-42237 actively exploited?
Yes. CISA added CVE-2021-42237 to its Known Exploited Vulnerabilities (KEV) catalog on 2022-03-25, with a federal remediation deadline of 2022-04-15. A KEV listing means real-world exploitation is confirmed, so patching this should be prioritized above many higher-CVSS bugs that aren't being exploited.
What is the CVSS score of CVE-2021-42237?
CVE-2021-42237 has a CVSS base score of 9.8 (Critical). Its vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Related vulnerabilities
- CVE-2025-53690 — Sitecore Multiple Products
- CVE-2019-9875 — Sitecore CMS and Experience Platform (XP)
- CVE-2019-9874 — Sitecore CMS and Experience Platform (XP)
- CVE-2021-23758 — Ajax.NET Professional Ajax.NET Professiona
- CVE-2026-63077 — JetBrains TeamCity
- CVE-2026-50522 — Microsoft SharePoint
Data source: NVD & CISA KEV. Shown as-is; nothing added. Last generated from NVD data — re-check the live tool for updates.
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