How severe is CVE-2018-16821?

CVE-2018-16821 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2018-16821 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-16821?

CVE-2018-16821 affects Seacms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-16821?

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

When was CVE-2018-16821 published?

CVE-2018-16821 was published on 2018-09-21 and last updated on 2026-06-17.

CVE-2018-16821

CVE-2018-16821 is a medium-severity vulnerability in Seacms with a CVSS 3.x base score of 5.3. 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-434.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (59th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Seacms
Published: 2018-09-21
Last modified: 2026-06-17

Description

SeaCMS 6.64 allows arbitrary directory listing via upload/admin/admin_template.php?path=../templets/../../ requests.

Frequently asked questions

What is CVE-2018-16821?: SeaCMS 6.64 allows arbitrary directory listing via upload/admin/admin_template.php?path=../templets/../../ requests.
How severe is CVE-2018-16821?: CVE-2018-16821 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2018-16821 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-16821?: CVE-2018-16821 affects Seacms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-16821?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-16821 published?: CVE-2018-16821 was published on 2018-09-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:seacms:seacms:6.64:*:*:*:*:*:*:*

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