How severe is CVE-2021-42655?

CVE-2021-42655 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-42655 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42655?

CVE-2021-42655 affects Sscms Siteserver Cms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-42655?

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-2021-42655 published?

CVE-2021-42655 was published on 2022-05-24 and last updated on 2026-06-17.

CVE-2021-42655

CVE-2021-42655 is a high-severity vulnerability in Sscms Siteserver Cms with a CVSS 3.x base score of 8.8. 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-89.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-89
Affected product: Sscms Siteserver Cms
Published: 2022-05-24
Last modified: 2026-06-17

Description

SiteServer CMS V6.15.51 is affected by a SQL injection vulnerability.

Frequently asked questions

What is CVE-2021-42655?: SiteServer CMS V6.15.51 is affected by a SQL injection vulnerability.
How severe is CVE-2021-42655?: CVE-2021-42655 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-42655 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42655?: CVE-2021-42655 affects Sscms Siteserver Cms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-42655?: 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-2021-42655 published?: CVE-2021-42655 was published on 2022-05-24 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:sscms:siteserver_cms:6.15.51:*:*:*:*:*:*:*

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