How severe is CVE-2021-47937?

CVE-2021-47937 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-47937 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2021-47937?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2021-47937 have an EU (EUVD) identifier?

Yes. CVE-2021-47937 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34798.

When was CVE-2021-47937 published?

CVE-2021-47937 was published on 2026-05-10 and last updated on 2026-06-17.

CVE-2021-47937

CVE-2021-47937 is a high-severity vulnerability with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-434.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v4: 8.7
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-34798
Weakness: CWE-434
Published: 2026-05-10
Last modified: 2026-06-17

Description

e107 CMS 2.3.0 contains a remote code execution vulnerability that allows authenticated users with theme installation permissions to execute arbitrary commands by uploading malicious theme files. Attackers can upload a crafted theme package through the theme.php endpoint that deploys a web shell to the e107_themes directory, then execute system commands via the payload.php script.

Frequently asked questions

What is CVE-2021-47937?: e107 CMS 2.3.0 contains a remote code execution vulnerability that allows authenticated users with theme installation permissions to execute arbitrary commands by uploading malicious theme files. Attackers can upload a crafted theme package through the theme.php endpoint that deploys a web shell to the e107_themes directory, then execute system commands via the payload.php script.
How severe is CVE-2021-47937?: CVE-2021-47937 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-47937 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2021-47937?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2021-47937 have an EU (EUVD) identifier?: Yes. CVE-2021-47937 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34798.
When was CVE-2021-47937 published?: CVE-2021-47937 was published on 2026-05-10 and last updated on 2026-06-17.

References

Other CWE-434 (Unrestricted Upload of File with Dangerous Type) vulnerabilities

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CVE-2026-48276 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Unrestricted Upload of File with Dangerous Type…
CVE-2026-57700 — Critical (CVSS 10.0): Unrestricted Upload of File with Dangerous Type vulnerability in Daan.Dev OMGF Pro allows Using Malicious Files. This…
CVE-2025-69129 — Critical (CVSS 10.0): Unauthenticated Arbitrary File Upload in WordPress & WooCommerce Scraper Plugin, Import Data from Any Site <= 1.0.7…
CVE-2026-40772 — Critical (CVSS 10.0): Unauthenticated Arbitrary File Upload in GeekyBot <= 1.2.2 versions.
CVE-2026-40412 — Critical (CVSS 10.0): Unrestricted upload of file with dangerous type in Azure Orbital Spatio allows an unauthorized attacker to execute code…

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