How severe is CVE-2026-71573?

CVE-2026-71573 has a CVSS 3.x base score of 8.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2026-71573 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-71573?

CVE-2026-71573 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-71573?

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-2026-71573 published?

CVE-2026-71573 was published on 2026-08-18 and last updated on 2026-09-03.

CVE-2026-71573

CVE-2026-71573 is a high-severity vulnerability in Joomla Joomla! with a CVSS 3.x base score of 8.3. 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-93.

Key facts

Severity: High (CVSS 3.x base score 8.3)
CVSS v4: 6.9
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-93
Affected product: Joomla Joomla!
Published: 2026-08-18
Last modified: 2026-09-03

Description

Joomla! Core - [20260802] - Improper CORS origin validation in Joomla 4.0.0-5.4.7, 6.0.0-6.1.2 - An improper implementation prevented configured CORS origins from being properly validated in CORS requests.

Frequently asked questions

What is CVE-2026-71573?: Joomla! Core - [20260802] - Improper CORS origin validation in Joomla 4.0.0-5.4.7, 6.0.0-6.1.2 - An improper implementation prevented configured CORS origins from being properly validated in CORS requests.
How severe is CVE-2026-71573?: CVE-2026-71573 has a CVSS 3.x base score of 8.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2026-71573 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-71573?: CVE-2026-71573 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-71573?: 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-2026-71573 published?: CVE-2026-71573 was published on 2026-08-18 and last updated on 2026-09-03.

References

Affected products (1)

cpe:2.3:a:joomla:joomla\!:*:*:*:*:*:*:*:*

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