CVE-2021-42237

highpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.976 · 100 %ileexploit · weaponizedEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV · 4 exploits · weaponized

Likely / severe?

97.6% (100th) EPSS

CVSS 10 · high

Is it mine?

6 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

added 2022-03-25remediate by 2022-04-15

required action Apply updates per vendor instructions.

EPSS · scored 2026-10-27

Sitecore XP Remote Command Execution Vulnerability

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.

cvss

Technical severity, 0–10. One row per scoring source.

10.0

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 9.8–10

v2.010highAV:N/AC:L/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 10 · impact 10

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19.8criticalAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondaryexploitability 3.9 · impact 5.9

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: active · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-502USprimaryCWE-502US

ATT&CK techniques

ATT&CK techniques this enables or maps to.

T1059Command and Scripting Interpreter — CVE 2021-42237related to a remote code execution vulnerability through insecure deserialization. primary impact

exploits (4)

Public proof-of-concept and weaponised exploit code.

exploit/windows/http/sitecore_xp_cve_2021_42237Sitecore Experience Platform (XP) PreAuth Deserialization RCEweaponized · metasploit
ItsIgnacioPortal/CVE-2021-42237An exploit/PoC for CVE-2021-42237PoC · poc_in_github
crankyyash/SiteCore-RCE-DetectionFor detection of sitecore RCE - CVE-2021-42237PoC · poc_in_github
vesperp/CVE-2021-42237-SiteCore-XPvesperp/CVE-2021-42237-SiteCore-XPPoC · poc_in_github

affected products (6)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
Sitecore Sitecore Experience Platform≤ 9.0 rev. 171002fstec_bduRU
sitecore experience platform= 7.5nvdUScpe:2.3:a:sitecore:experience_platform:*:*:*:*:*:*:*:*
sitecore experience platform= 8.0nvdUScpe:2.3:a:sitecore:experience_platform:*:*:*:*:*:*:*:*
sitecore experience platform= 8.1nvdUScpe:2.3:a:sitecore:experience_platform:*:*:*:*:*:*:*:*
sitecore experience platform= 8.2nvdUScpe:2.3:a:sitecore:experience_platform:*:*:*:*:*:*:*:*

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2021-11-05modified 2026-07-09

related (3,745)

Related entries.

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+3740 more

references (13)

External citations — patches, advisories, analysis.

scry

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