CVE-2021-42237
Confirmed PUBLISHEDSitecore 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...
Recommended Action
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
At a Glance
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.
- CVE Published
- Nov 05, 2021
- Exploitation Reported
- Mar 25, 2022
- CVSS
- 9.8 Critical
- EPSS
- 97.9%
Affected Versions
| Vendor | Product | Version | Status |
|---|---|---|---|
| n/a |
n/a
|
n/a |
Affected |
CVE References
- support.sitecore.com/kb support.sitecore.com · CVE Record https://support.sitecore.com/kb?id=kb_article_view&sysparm_article=KB...
- blog.assetnote.io/2021/11/02/sitecore-rce blog.assetnote.io · CVE Record https://blog.assetnote.io/2021/11/02/sitecore-rce/
- packetstormsecurity.com/files/164988/Sitecore-Experience-Platform-XP... packetstormsecurity.com · CVE Record http://packetstormsecurity.com/files/164988/Sitecore-Experience-Platf...
Recommended Actions
- Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
- Check enrichment artifacts for scanner coverage and available PoCs before rolling remediation validation.
- Use the Pro API to automate enrichment, telemetry, and workflow delivery for VM, SOC, and CTI pipelines.
Known Exploited Vulnerability Sources
Catalogues that list this CVE as a known exploited vulnerability.
Per-source evidence links for KEV attestations are available through the KEVIntel Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| CISA First | 2022-03-25 00:00 UTC |
| CVE | 2026-07-05 00:30 UTC |
| The Shadowserver | 2026-07-08 00:00 UTC |
Scanner Artifacts
Nuclei and Metasploit references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-42237.yaml | Apr 25, 2025 |
| Metasploit | https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/http/sitecore_xp_cve_2021_42237.rb | Apr 28, 2025 |
Virtual Patch
Compensating WAF rules to help reduce exposure to this CVE. Rule content and deployable vendor exports are available with KEVIntel Enterprise.
KEVIntel does not currently have a virtual patch for this CVE. When available, KEVIntel virtual patches ship as deployable ModSecurity, Cloudflare, and AWS WAF rules.
Enterprise feature. Virtual patch rule content and deployable vendor exports (ModSecurity, Cloudflare, AWS WAF) are available to KEVIntel Enterprise users.
CVSS Scores
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
AV:N/AC:L/Au:N/C:C/I:C/A:C
Exploitation Status
Exploited in the wild
Recorded 2022-03-25 00:00:00 UTC · CISA
Used in malware
Recorded 2022-03-25 00:00:00 UTC · CISA
Proof of concept available
Recorded 2022-01-16 05:22:30 UTC · GitHub
Weaknesses (CWE)
-
Deserialization of Untrusted Data
Scanner Integrations
| Scanner | Reference | Detected |
|---|---|---|
| Metasploit | https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/http/sitecore_xp_cve_2021_42237.rb | Apr 28, 2025 |
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-42237.yaml | Apr 25, 2025 |
Potential Proof of Concepts
These PoCs are unverified and could contain malware. Use at your own risk.
github · Created 2022-01-16 05:22:30 UTC · 12 stars
An exploit/PoC for CVE-2021-42237
nuclei · Created Unknown
Timeline
Key exploitation, disclosure, scanner coverage, and KEV attestation events for this CVE.
-
00:00 UTC 12 days ago00:00 UTC · 12 days ago
KEV confirmed by The Shadowserver
Exploitation attested by an external source
-
00:30 UTC 15 days ago00:30 UTC · 15 days ago
KEV confirmed by CVE
Exploitation attested by an external source
-
15:02 UTC about 1 year ago15:02 UTC · about 1 year ago
Metasploit module available
Exploit module available
-
00:00 UTC about 1 year ago00:00 UTC · about 1 year ago
Nuclei template available
Scanner coverage available
-
00:00 UTC over 4 years ago00:00 UTC · over 4 years ago
Added to CISA KEV
Listed in the CISA Known Exploited Vulnerabilities catalog
-
00:00 UTC over 4 years ago00:00 UTC · over 4 years ago
First public exploitation report
Exploit observed in malware
-
05:22 UTC over 4 years ago05:22 UTC · over 4 years ago
Public PoC available
Public proof-of-concept code published
-
09:51 UTC over 4 years ago09:51 UTC · over 4 years ago
CVE published
Vulnerability disclosed publicly
-
00:00 UTC almost 5 years ago00:00 UTC · almost 5 years ago
CVE ID reserved
Identifier reserved by the CNA
Automate This Intelligence with the Pro API
Confidence scoring, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
Pro API Example
GET /api/v2/pro/kevs/CVE-2021-42237
{
"cve_id": "CVE-2021-42237",
"title": "Sitecore XP 7.5 Initial Release to Sitecore XP 8.2 Update-7 is vulnerable to ...",
"affected_vendor": "Sitecore",
"affected_product": "Sitecore XP",
"affected_versions": [
{ "vendor": "...", "product": "...", "status": "affected", "display_label": "..." }
],
"confidence": "Confirmed",
"cvss_score": 9.8,
"epss_score": 0.97904,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "...": "Pro API fields" },
"proof_of_concepts": [ "..." ],
"scanner_integrations": [ "..." ]
}