How severe is CVE-2015-6734?

CVE-2015-6734 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2015-6734 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-6734?

CVE-2015-6734 primarily affects Mediawiki. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2015-6734?

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

When was CVE-2015-6734 published?

CVE-2015-6734 was published on 2015-09-01 and last updated on 2026-06-17.

CVE-2015-6734

CVE-2015-6734 is a medium-severity vulnerability in Mediawiki with a CVSS 2.0 base score of 4.3. 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-79.

Key facts

Severity: Medium (CVSS 2.0 base score 4.3)
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Mediawiki
Published: 2015-09-01
Last modified: 2026-06-17

Description

Cross-site scripting (XSS) vulnerability in contrib/cssgen.php in the GeSHi, as used in the SyntaxHighlight_GeSHi extension and MediaWiki before 1.23.10, 1.24.x before 1.24.3, and 1.25.x before 1.25.2, allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.

Frequently asked questions

What is CVE-2015-6734?: Cross-site scripting (XSS) vulnerability in contrib/cssgen.php in the GeSHi, as used in the SyntaxHighlight_GeSHi extension and MediaWiki before 1.23.10, 1.24.x before 1.24.3, and 1.25.x before 1.25.2, allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.
How severe is CVE-2015-6734?: CVE-2015-6734 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2015-6734 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-6734?: CVE-2015-6734 primarily affects Mediawiki. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2015-6734?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-6734 published?: CVE-2015-6734 was published on 2015-09-01 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:mediawiki:mediawiki:*:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.24.0:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.24.1:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.24.2:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.25.0:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.25.1:*:*:*:*:*:*:*

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