How severe is CVE-2021-23837?

CVE-2021-23837 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-23837 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23837?

CVE-2021-23837 affects Flatcore. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23837?

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

When was CVE-2021-23837 published?

CVE-2021-23837 was published on 2021-01-15 and last updated on 2026-06-17.

CVE-2021-23837

CVE-2021-23837 is a medium-severity vulnerability in Flatcore with a CVSS 3.x base score of 6.5. 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: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-89
Affected product: Flatcore
Published: 2021-01-15
Last modified: 2026-06-17

Description

An issue was discovered in flatCore before 2.0.0 build 139. A time-based blind SQL injection was identified in the selected_folder HTTP request body parameter for the acp interface. The affected parameter (which retrieves the file contents of the specified folder) was found to be accepting malicious user input without proper sanitization, thus leading to SQL injection. Database related information can be successfully retrieved.

Frequently asked questions

What is CVE-2021-23837?: An issue was discovered in flatCore before 2.0.0 build 139. A time-based blind SQL injection was identified in the selected_folder HTTP request body parameter for the acp interface. The affected parameter (which retrieves the file contents of the specified folder) was found to be accepting malicious user input without proper sanitization, thus leading to SQL injection. Database related information can be successfully retrieved.
How severe is CVE-2021-23837?: CVE-2021-23837 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-23837 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23837?: CVE-2021-23837 affects Flatcore. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23837?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-23837 published?: CVE-2021-23837 was published on 2021-01-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:flatcore:flatcore:*:*:*:*:*:*:*:*

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