How severe is CVE-2020-12256?

CVE-2020-12256 has a CVSS score of 5.4/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2020-12256?

Affected package information for CVE-2020-12256 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2020-12256?

No fixed version has been published for CVE-2020-12256 yet. Monitor the advisory for updates, apply mitigations recommended by the vendor, and use O3 Security to track when a fix becomes available in your stack.

Is CVE-2020-12256 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2020-12256, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2020-12256?

CVE-2020-12256 has an EPSS (Exploit Prediction Scoring System) score of 92.8%, placing it in the 100th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

What type of vulnerability is CVE-2020-12256?

CVE-2020-12256 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Which products and versions are affected by CVE-2020-12256?

CVE-2020-12256 affects rconfig rconfig (1 version, e.g. 3.9.4). Check the affected-products list on this page against your deployed version to confirm exposure.

Is there exploit tooling available for CVE-2020-12256?

A Nuclei detection template exists for CVE-2020-12256, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2020-12256 published, and has it been updated?

CVE-2020-12256 was published on May 18, 2020 and was last updated on November 21, 2024. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2020-12256

MEDIUM

rConfig 3.9.4 is vulnerable to reflected XSS. The devicemgmnt.php file improperly validates user input. An attacker can exploit this by crafting arbitrary JavaScript in the deviceId…

Published

May 18, 2020

Updated

Nov 21, 2024

Affected

0 pkgs

Patched

None yet

Exploits

1 known

EPSS Exploitation Probability

via FIRST.org ↗

92.8%probability of exploitation in next 30 days

Very High Risk100th percentile+37.90%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

rConfig 3.9.4 is vulnerable to reflected XSS. The devicemgmnt.php file improperly validates user input. An attacker can exploit this by crafting arbitrary JavaScript in the deviceId GET parameter to devicemgmnt.php.

Affected Products

1 product · 1 configurations

Application

rconfigrconfig

1 version

3.9.4

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

rConfig 3.9.4 is vulnerable to reflected XSS. The devicemgmnt.php file i…

gist.github.comNVDMay 2020

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2020-12256 in your stack?

O3 detects CVE-2020-12256 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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