How severe is CVE-2016-9838?

CVE-2016-9838 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-2016-9838 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 14% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-9838?

CVE-2016-9838 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-9838?

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-2016-9838 published?

CVE-2016-9838 was published on 2016-12-16 and last updated on 2026-06-17.

CVE-2016-9838

CVE-2016-9838 is a high-severity vulnerability in Joomla Joomla! with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 14% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-284.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 14% (96th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Joomla Joomla!
Published: 2016-12-16
Last modified: 2026-06-17

Description

An issue was discovered in components/com_users/models/registration.php in Joomla! before 3.6.5. Incorrect filtering of registration form data stored to the session on a validation error enables a user to gain access to a registered user's account and reset the user's group mappings, username, and password, as demonstrated by submitting a form that targets the `registration.register` task.

Frequently asked questions

What is CVE-2016-9838?: An issue was discovered in components/com_users/models/registration.php in Joomla! before 3.6.5. Incorrect filtering of registration form data stored to the session on a validation error enables a user to gain access to a registered user's account and reset the user's group mappings, username, and password, as demonstrated by submitting a form that targets the `registration.register` task.
How severe is CVE-2016-9838?: CVE-2016-9838 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-2016-9838 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 14% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-9838?: CVE-2016-9838 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-9838?: 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-2016-9838 published?: CVE-2016-9838 was published on 2016-12-16 and last updated on 2026-06-17.

References

Affected products (1)

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

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