How severe is CVE-2021-23835?

CVE-2021-23835 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-23835 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23835?

CVE-2021-23835 affects Flatcore. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23835?

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

When was CVE-2021-23835 published?

CVE-2021-23835 was published on 2021-01-15 and last updated on 2026-06-17.

CVE-2021-23835

CVE-2021-23835 is a medium-severity vulnerability in Flatcore with a CVSS 3.x base score of 4.9. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 4.9)
CVSS v2: 4.0
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
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 local file disclosure vulnerability was identified in the docs_file HTTP request body parameter for the acp interface. This can be exploited with admin access rights. The affected parameter (which retrieves the contents of the specified file) was found to be accepting malicious user input without proper sanitization, thus leading to retrieval of backend server sensitive files, e.g., /etc/passwd, SQLite database files, PHP source code, etc.

Frequently asked questions

What is CVE-2021-23835?: An issue was discovered in flatCore before 2.0.0 build 139. A local file disclosure vulnerability was identified in the docs_file HTTP request body parameter for the acp interface. This can be exploited with admin access rights. The affected parameter (which retrieves the contents of the specified file) was found to be accepting malicious user input without proper sanitization, thus leading to retrieval of backend server sensitive files, e.g., /etc/passwd, SQLite database files, PHP source code, etc.
How severe is CVE-2021-23835?: CVE-2021-23835 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-23835 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23835?: CVE-2021-23835 affects Flatcore. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23835?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-23835 published?: CVE-2021-23835 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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