CVE-2021-27309

CVE-2021-27309 is a medium-severity vulnerability in Csphere Clansphere with a CVSS 3.x base score of 6.1. 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

Description

Clansphere CMS 2011.4 allows unauthenticated reflected XSS via "module" parameter.

Frequently asked questions

What is CVE-2021-27309?
Clansphere CMS 2011.4 allows unauthenticated reflected XSS via "module" parameter.
How severe is CVE-2021-27309?
CVE-2021-27309 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-27309 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27309?
CVE-2021-27309 affects Csphere Clansphere. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27309?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-27309 published?
CVE-2021-27309 was published on 2021-03-23 and last updated on 2026-06-17.

References

Affected products (1)

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