How severe is CVE-2018-15882?

CVE-2018-15882 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-15882 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-15882?

CVE-2018-15882 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-15882?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2018-15882 published?

CVE-2018-15882 was published on 2018-08-29 and last updated on 2026-06-17.

CVE-2018-15882

CVE-2018-15882 is a critical-severity vulnerability in Joomla Joomla! with a CVSS 3.x base score of 9.8. 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-434.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Joomla Joomla!
Published: 2018-08-29
Last modified: 2026-06-17

Description

An issue was discovered in Joomla! before 3.8.12. Inadequate checks in the InputFilter class could allow specifically prepared phar files to pass the upload filter.

Frequently asked questions

What is CVE-2018-15882?: An issue was discovered in Joomla! before 3.8.12. Inadequate checks in the InputFilter class could allow specifically prepared phar files to pass the upload filter.
How severe is CVE-2018-15882?: CVE-2018-15882 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-15882 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-15882?: CVE-2018-15882 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-15882?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2018-15882 published?: CVE-2018-15882 was published on 2018-08-29 and last updated on 2026-06-17.

References

Affected products (1)

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

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