How severe is CVE-2020-11066?

CVE-2020-11066 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.

Is CVE-2020-11066 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-11066?

CVE-2020-11066 affects Typo3. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-11066?

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.

When was CVE-2020-11066 published?

CVE-2020-11066 was published on 2020-05-14 and last updated on 2026-06-17.

CVE-2020-11066

CVE-2020-11066 is a high-severity vulnerability in Typo3 with a CVSS 3.x base score of 8.7. 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-1321.

Key facts

Severity: High (CVSS 3.x base score 8.7)
CVSS v2: 6.4
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1321
Affected product: Typo3
Published: 2020-05-14
Last modified: 2026-06-17

Description

In TYPO3 CMS greater than or equal to 9.0.0 and less than 9.5.17 and greater than or equal to 10.0.0 and less than 10.4.2, calling unserialize() on malicious user-submitted content can lead to modification of dynamically-determined object attributes and result in triggering deletion of an arbitrary directory in the file system, if it is writable for the web server. It can also trigger message submission via email using the identity of the web site (mail relay). Another insecure deserialization vulnerability is required to actually exploit mentioned aspects. This has been fixed in 9.5.17 and 10.4.2.

Frequently asked questions

What is CVE-2020-11066?: In TYPO3 CMS greater than or equal to 9.0.0 and less than 9.5.17 and greater than or equal to 10.0.0 and less than 10.4.2, calling unserialize() on malicious user-submitted content can lead to modification of dynamically-determined object attributes and result in triggering deletion of an arbitrary directory in the file system, if it is writable for the web server. It can also trigger message submission via email using the identity of the web site (mail relay). Another insecure deserialization vulnerability is required to actually exploit mentioned aspects. This has been fixed in 9.5.17 and 10.4.2.
How severe is CVE-2020-11066?: CVE-2020-11066 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2020-11066 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-11066?: CVE-2020-11066 affects Typo3. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-11066?: 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.
When was CVE-2020-11066 published?: CVE-2020-11066 was published on 2020-05-14 and last updated on 2026-06-17.

References

https://github.com/TYPO3/TYPO3.CMS/security/advisories/GHSA-2rxh-h6h9-qrqc

Affected products (1)

cpe:2.3:a:typo3:typo3:*:*:*:*:*:*:*:*

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