CVE-2021-40555
CVE-2021-40555 is a medium-severity vulnerability in Flatcore with a CVSS 3.x base score of 5.4. 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
- Severity: Medium (CVSS 3.x base score 5.4)
- EPSS exploit prediction: 0% (35th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-79
- Affected product: Flatcore
- Published:
- Last modified:
Description
Cross site scripting (XSS) vulnerability in flatCore-CMS 2.2.15 allows attackers to execute arbitrary code via description field on the new page creation form.
Frequently asked questions
- What is CVE-2021-40555?
- Cross site scripting (XSS) vulnerability in flatCore-CMS 2.2.15 allows attackers to execute arbitrary code via description field on the new page creation form.
- How severe is CVE-2021-40555?
- CVE-2021-40555 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2021-40555 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-40555?
- CVE-2021-40555 affects Flatcore. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-40555?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-40555 published?
- CVE-2021-40555 was published on 2023-02-16 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:flatcore:flatcore:2.0.7:*:*:*:*:*:*:*
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