CVE-2017-6900

CVE-2017-6900 is a critical-severity vulnerability in Riello-ups Netman 204 Firmware with a CVSS 3.x base score of 9.8. 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-255.

Key facts

Description

An issue was discovered in Riello NetMan 204 14-2 and 15-2. The issue is with the login script and wrongpass Python script used for authentication. When calling wrongpass, the variables $VAL0 and $VAL1 should be enclosed in quotes to prevent the potential for Bash command injection. Further to this, VAL0 and VAL1 should be sanitised to ensure they do not contain malicious characters. Passing it the username of '-' will cause it to time out and log the user in because of poor error handling. This will log the attacker in as an administrator where the telnet / ssh services can be enabled, and the credentials for local users can be reset. Also, login.cgi accepts the username as a GET parameter, so login can be achieved by browsing to the /cgi-bin/login.cgi?username=-%20a URI.

Frequently asked questions

What is CVE-2017-6900?
An issue was discovered in Riello NetMan 204 14-2 and 15-2. The issue is with the login script and wrongpass Python script used for authentication. When calling wrongpass, the variables $VAL0 and $VAL1 should be enclosed in quotes to prevent the potential for Bash command injection. Further to this, VAL0 and VAL1 should be sanitised to ensure they do not contain malicious characters. Passing it the username of '-' will cause it to time out and log the user in because of poor error handling. This will log the attacker in as an administrator where the telnet / ssh services can be enabled, and the credentials for local users can be reset. Also, login.cgi accepts the username as a GET parameter, so login can be achieved by browsing to the /cgi-bin/login.cgi?username=-%20a URI.
How severe is CVE-2017-6900?
CVE-2017-6900 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2017-6900 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-6900?
CVE-2017-6900 primarily affects Riello-ups Netman 204 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-6900?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2017-6900 published?
CVE-2017-6900 was published on 2019-07-03 and last updated on 2026-06-17.

References

Affected products (2)

More vulnerabilities in Riello-ups Netman 204 Firmware

All CVEs affecting Riello-ups Netman 204 Firmware →

Other CWE-255 (Credentials Management Errors) vulnerabilities

Browse all CWE-255 (Credentials Management Errors) vulnerabilities →