How severe is CVE-2016-6331?

CVE-2016-6331 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 high, integrity none, and availability none.

Is CVE-2016-6331 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-6331?

CVE-2016-6331 primarily affects Mediawiki. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-6331?

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-2016-6331 published?

CVE-2016-6331 was published on 2017-04-20 and last updated on 2026-06-17.

CVE-2016-6331

CVE-2016-6331 is a high-severity vulnerability in Mediawiki 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-284.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Mediawiki
Published: 2017-04-20
Last modified: 2026-06-17

Description

ApiParse in MediaWiki before 1.23.15, 1.26.x before 1.26.4, and 1.27.x before 1.27.1 allows remote attackers to bypass intended per-title read restrictions via a parse action to api.php.

Frequently asked questions

What is CVE-2016-6331?: ApiParse in MediaWiki before 1.23.15, 1.26.x before 1.26.4, and 1.27.x before 1.27.1 allows remote attackers to bypass intended per-title read restrictions via a parse action to api.php.
How severe is CVE-2016-6331?: CVE-2016-6331 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 high, integrity none, and availability none.
Is CVE-2016-6331 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-6331?: CVE-2016-6331 primarily affects Mediawiki. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-6331?: 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-2016-6331 published?: CVE-2016-6331 was published on 2017-04-20 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:mediawiki:mediawiki:*:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.26.0:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.26.1:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.26.2:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.26.3:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.26.4:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.27.0:*:*:*:*:*:*:*

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