How severe is CVE-2021-26040?

CVE-2021-26040 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.

Is CVE-2021-26040 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26040?

CVE-2021-26040 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26040?

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.

When was CVE-2021-26040 published?

CVE-2021-26040 was published on 2021-08-24 and last updated on 2026-06-17.

CVE-2021-26040

CVE-2021-26040 is a critical-severity vulnerability in Joomla Joomla! with a CVSS 3.x base score of 9.1. 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-863.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v2: 6.4
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Joomla Joomla!
Published: 2021-08-24
Last modified: 2026-06-17

Description

An issue was discovered in Joomla! 4.0.0. The media manager does not correctly check the user's permissions before executing a file deletion command.

Frequently asked questions

What is CVE-2021-26040?: An issue was discovered in Joomla! 4.0.0. The media manager does not correctly check the user's permissions before executing a file deletion command.
How severe is CVE-2021-26040?: CVE-2021-26040 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2021-26040 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26040?: CVE-2021-26040 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26040?: 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.
When was CVE-2021-26040 published?: CVE-2021-26040 was published on 2021-08-24 and last updated on 2026-06-17.

References

https://developer.joomla.org/security-centre/861-20210801-core-insufficient-access-control-for-com-media-deletion-endpoint

Affected products (1)

cpe:2.3:a:joomla:joomla\!:4.0.0:-:*:*:*:*:*:*

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