How severe is CVE-2021-26038?

CVE-2021-26038 has a CVSS 3.x base score of 7.5, rated high 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 none.

Is CVE-2021-26038 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26038?

CVE-2021-26038 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26038?

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-2021-26038 published?

CVE-2021-26038 was published on 2021-07-07 and last updated on 2026-06-17.

CVE-2021-26038

CVE-2021-26038 is a high-severity vulnerability in Joomla Joomla! with a CVSS 3.x base score of 7.5. 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-754.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-754
Affected product: Joomla Joomla!
Published: 2021-07-07
Last modified: 2026-06-17

Description

An issue was discovered in Joomla! 2.5.0 through 3.9.27. Install action in com_installer lack the required hardcoded ACL checks for superusers. A default system is not affected cause the default ACL for com_installer is limited to super users already.

Frequently asked questions

What is CVE-2021-26038?: An issue was discovered in Joomla! 2.5.0 through 3.9.27. Install action in com_installer lack the required hardcoded ACL checks for superusers. A default system is not affected cause the default ACL for com_installer is limited to super users already.
How severe is CVE-2021-26038?: CVE-2021-26038 has a CVSS 3.x base score of 7.5, rated high 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 none.
Is CVE-2021-26038 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26038?: CVE-2021-26038 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26038?: 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-2021-26038 published?: CVE-2021-26038 was published on 2021-07-07 and last updated on 2026-06-17.

References

https://developer.joomla.org/security-centre/859-20210704-core-privilege-escalation-through-com-installer.html

Affected products (1)

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

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