How severe is CVE-2020-5811?

CVE-2020-5811 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2020-5811 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5811?

CVE-2020-5811 affects Umbraco Umbraco Cms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-5811?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-5811 published?

CVE-2020-5811 was published on 2020-12-30 and last updated on 2026-06-17.

CVE-2020-5811

CVE-2020-5811 is a medium-severity vulnerability in Umbraco Umbraco Cms with a CVSS 3.x base score of 6.5. 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-22.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 9% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-22
Affected product: Umbraco Umbraco Cms
Published: 2020-12-30
Last modified: 2026-06-17

Description

An authenticated path traversal vulnerability exists during package installation in Umbraco CMS <= 8.9.1 or current, which could result in arbitrary files being written outside of the site home and expected paths when installing an Umbraco package.

Frequently asked questions

What is CVE-2020-5811?: An authenticated path traversal vulnerability exists during package installation in Umbraco CMS <= 8.9.1 or current, which could result in arbitrary files being written outside of the site home and expected paths when installing an Umbraco package.
How severe is CVE-2020-5811?: CVE-2020-5811 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2020-5811 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5811?: CVE-2020-5811 affects Umbraco Umbraco Cms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-5811?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-5811 published?: CVE-2020-5811 was published on 2020-12-30 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:umbraco:umbraco_cms:*:*:*:*:*:*:*:*

More vulnerabilities in Umbraco Umbraco Cms

CVE-2025-67288 — Critical (CVSS 10.0): An arbitrary file upload vulnerability in Umbraco CMS v16.3.3 allows attackers to execute arbitrary code by uploading a…
CVE-2012-10054 — Critical (CVSS 9.8): Umbraco CMS versions prior to 4.7.1 are vulnerable to unauthenticated remote code execution via the codeEditorSave.asmx…
CVE-2014-10074 — Critical (CVSS 9.8): Umbraco before 7.2.0 has a remote PHP code execution vulnerability because…
CVE-2012-1301 — Critical (CVSS 9.8): The FeedProxy.aspx script in Umbraco 4.7.0 allows remote attackers to proxy requests on their behalf via the "url"…
CVE-2025-32017 — High (CVSS 8.8): Umbraco is a free and open source .NET content management system. Authenticated users to the Umbraco backoffice are…
CVE-2020-9471 — High (CVSS 8.8): Umbraco Cloud 8.5.3 allows an authenticated file upload (and consequently Remote Code Execution) via the Install…

All CVEs affecting Umbraco Umbraco Cms →

Other CWE-22 (Path Traversal) vulnerabilities

CVE-2026-48282 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Limitation of a Pathname to a Restricted…
CVE-2026-54917 — Critical (CVSS 10.0): SeaweedFS is a distributed storage system for object storage (S3), file systems, and Iceberg tables. Prior to 4.30, the…
CVE-2026-11429 — Critical (CVSS 10.0): Two endpoints in the Vault Service ScriptsController, shared by Altium Enterprise Server and Altium 365, accept file…
CVE-2026-34909 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit a Path Traversal vulnerability found in UniFi OS devices to…
CVE-2026-7411 — Critical (CVSS 10.0): In Eclipse BaSyx Java Server SDK versions prior to 2.0.0-milestone-10, inadequate path normalization in the Submodel…
CVE-2026-36767 — Critical (CVSS 10.0): A path traversal vulnerability in the /content/images/add endpoint of shopizer v3.2.5 allows attackers write arbitrary…

Browse all CWE-22 (Path Traversal) vulnerabilities →