How severe is CVE-2021-26029?

CVE-2021-26029 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2021-26029 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26029?

CVE-2021-26029 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26029?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-26029 published?

CVE-2021-26029 was published on 2021-03-04 and last updated on 2026-06-17.

CVE-2021-26029

CVE-2021-26029 is a medium-severity vulnerability in Joomla Joomla! with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Joomla Joomla!
Published: 2021-03-04
Last modified: 2026-06-17

Description

An issue was discovered in Joomla! 1.6.0 through 3.9.24. Inadequate filtering of form contents could allow to overwrite the author field.

Frequently asked questions

What is CVE-2021-26029?: An issue was discovered in Joomla! 1.6.0 through 3.9.24. Inadequate filtering of form contents could allow to overwrite the author field.
How severe is CVE-2021-26029?: CVE-2021-26029 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-26029 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26029?: CVE-2021-26029 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26029?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-26029 published?: CVE-2021-26029 was published on 2021-03-04 and last updated on 2026-06-17.

References

https://developer.joomla.org/security-centre/849-20210309-core-inadequate-filtering-of-form-contents-could-allow-to-overwrite-the-author-field.html

Affected products (1)

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

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