How severe is CVE-2016-9021?

CVE-2016-9021 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-2016-9021 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-9021?

CVE-2016-9021 affects Exponentcms Exponent Cms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-9021?

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-2016-9021 published?

CVE-2016-9021 was published on 2020-12-31 and last updated on 2026-06-17.

CVE-2016-9021

CVE-2016-9021 is a critical-severity vulnerability in Exponentcms Exponent Cms 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-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Exponentcms Exponent Cms
Published: 2020-12-31
Last modified: 2026-06-17

Description

Exponent CMS before 2.6.0 has improper input validation in storeController.php.

Frequently asked questions

What is CVE-2016-9021?: Exponent CMS before 2.6.0 has improper input validation in storeController.php.
How severe is CVE-2016-9021?: CVE-2016-9021 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-2016-9021 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-9021?: CVE-2016-9021 affects Exponentcms Exponent Cms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-9021?: 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-2016-9021 published?: CVE-2016-9021 was published on 2020-12-31 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:exponentcms:exponent_cms:*:*:*:*:*:*:*:*

More vulnerabilities in Exponentcms Exponent Cms

CVE-2016-9026 — Critical (CVSS 9.8): Exponent CMS before 2.6.0 has improper input validation in fileController.php.
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