How severe is CVE-2020-26227?

CVE-2020-26227 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-26227 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-26227?

CVE-2020-26227 affects Typo3. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-26227?

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

When was CVE-2020-26227 published?

CVE-2020-26227 was published on 2020-11-23 and last updated on 2026-06-17.

CVE-2020-26227

CVE-2020-26227 is a medium-severity vulnerability in Typo3 with a CVSS 3.x base score of 6.1. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Typo3
Published: 2020-11-23
Last modified: 2026-06-17

Description

TYPO3 is an open source PHP based web content management system. In TYPO3 before versions 9.5.23 and 10.4.10 the system extension Fluid (typo3/cms-fluid) of the TYPO3 core is vulnerable to cross-site scripting passing user-controlled data as argument to Fluid view helpers. Update to TYPO3 versions 9.5.23 or 10.4.10 that fix the problem described.

Frequently asked questions

What is CVE-2020-26227?: TYPO3 is an open source PHP based web content management system. In TYPO3 before versions 9.5.23 and 10.4.10 the system extension Fluid (typo3/cms-fluid) of the TYPO3 core is vulnerable to cross-site scripting passing user-controlled data as argument to Fluid view helpers. Update to TYPO3 versions 9.5.23 or 10.4.10 that fix the problem described.
How severe is CVE-2020-26227?: CVE-2020-26227 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-26227 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-26227?: CVE-2020-26227 affects Typo3. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-26227?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-26227 published?: CVE-2020-26227 was published on 2020-11-23 and last updated on 2026-06-17.

References

Affected products (1)

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

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