CVE-2021-26036
CVE-2021-26036 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-20.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (70th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Joomla Joomla!
- Published:
- Last modified:
Description
An issue was discovered in Joomla! 2.5.0 through 3.9.27. Missing validation of input could lead to a broken usergroups table.
Frequently asked questions
- What is CVE-2021-26036?
- An issue was discovered in Joomla! 2.5.0 through 3.9.27. Missing validation of input could lead to a broken usergroups table.
- How severe is CVE-2021-26036?
- CVE-2021-26036 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 none, and availability high.
- Is CVE-2021-26036 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-26036?
- CVE-2021-26036 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-26036?
- 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-2021-26036 published?
- CVE-2021-26036 was published on 2021-07-07 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:joomla:joomla\!:*:*:*:*:*:*:*:*
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