How severe is CVE-2020-12255?

CVE-2020-12255 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-2020-12255 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 53% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-12255?

CVE-2020-12255 affects Rconfig. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-12255?

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-2020-12255 published?

CVE-2020-12255 was published on 2020-05-18 and last updated on 2026-06-17.

CVE-2020-12255

CVE-2020-12255 is a high-severity vulnerability in Rconfig with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 53% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-434.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 53% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Rconfig
Published: 2020-05-18
Last modified: 2026-06-17

Description

rConfig 3.9.4 is vulnerable to remote code execution due to improper validation in the file upload functionality. vendor.crud.php accepts a file upload by checking content-type without considering the file extension and header. Thus, an attacker can exploit this by uploading a .php file to vendor.php that contains arbitrary PHP code and changing the content-type to image/gif.

Frequently asked questions

What is CVE-2020-12255?: rConfig 3.9.4 is vulnerable to remote code execution due to improper validation in the file upload functionality. vendor.crud.php accepts a file upload by checking content-type without considering the file extension and header. Thus, an attacker can exploit this by uploading a .php file to vendor.php that contains arbitrary PHP code and changing the content-type to image/gif.
How severe is CVE-2020-12255?: CVE-2020-12255 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-2020-12255 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 53% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-12255?: CVE-2020-12255 affects Rconfig. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-12255?: 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-2020-12255 published?: CVE-2020-12255 was published on 2020-05-18 and last updated on 2026-06-17.

References

https://gist.github.com/farid007/9f6ad063645d5b1550298c8b9ae953ff

Affected products (1)

cpe:2.3:a:rconfig:rconfig:3.9.4:*:*:*:*:*:*:*

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