How severe is CVE-2026-21627?

CVE-2026-21627 has a CVSS 4.0 base score of 9.5, rated critical severity.

Is CVE-2026-21627 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-21627?

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

Does CVE-2026-21627 have an EU (EUVD) identifier?

Yes. CVE-2026-21627 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7670.

When was CVE-2026-21627 published?

CVE-2026-21627 was published on 2026-02-20 and last updated on 2026-06-17.

CVE-2026-21627

CVE-2026-21627 is a critical-severity vulnerability with a CVSS 4.0 base score of 9.5. 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-284.

Key facts

Severity: Critical (CVSS 4.0 base score 9.5)
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-7670
Weakness: CWE-284
Published: 2026-02-20
Last modified: 2026-06-17

Description

The vulnerability was rooted in how the Tassos Framework plugin handled specific AJAX requests through Joomla’s com_ajax entry point. Under certain conditions, internal framework functionality could be invoked without proper restriction.

Frequently asked questions

What is CVE-2026-21627?: The vulnerability was rooted in how the Tassos Framework plugin handled specific AJAX requests through Joomla’s com_ajax entry point. Under certain conditions, internal framework functionality could be invoked without proper restriction.
How severe is CVE-2026-21627?: CVE-2026-21627 has a CVSS 4.0 base score of 9.5, rated critical severity.
Is CVE-2026-21627 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-21627?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-21627 have an EU (EUVD) identifier?: Yes. CVE-2026-21627 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7670.
When was CVE-2026-21627 published?: CVE-2026-21627 was published on 2026-02-20 and last updated on 2026-06-17.

References

https://tassos.gr

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