Is CVE-2020-8657 (EyesOfNetwork Use of Hard-Coded Credentials) being exploited in the wild?

What the KEV listing tells you about real-world exposure

The practical meaning of a KEV listing is simple: the product flaw has crossed from theoretical risk into confirmed exploitation, so the question is no longer whether it matters, but whether your environment still exposes it. For this issue, the default API key behaviour is the reason the flaw is dangerous, because a shared secret that ships with the product can be copied, reused, or discovered without needing a separate credential compromise.

That is why CISA's Known Exploited Vulnerabilities Catalog is the right operational reference for urgency, while the product record should be checked against the vendor advisory for the exact remediation path. If the affected instance is exposed to users, partners, or the internet, treat the finding as a live exposure problem rather than a routine patching task.

Why hard-coded credentials change the response

Hard-coded credentials are not just a configuration weakness, they are an access-control failure because the same secret can be present across many installs and may be difficult to distinguish from legitimate traffic. Once the credential is embedded in the product, defenders lose the normal advantages of unique issuance, revocation, and auditability, which means compromise can persist even after the software itself is updated.

For this reason, remediation usually has two parts: remove or replace the embedded secret and then confirm that nothing else in the environment still trusts it. If the same API key was used broadly, the exposure may extend beyond the application itself into integrations, automation, or adjacent systems that accepted the key as proof of trust.

What to check before and after you remediate

Start by confirming whether any EyesOfNetwork deployment is reachable, active, and still using the default API key behaviour. Then look for signs that the key was already used outside normal administration patterns, especially unusual authentication attempts, configuration changes, or requests that would not be expected from a known operator or automation path.

Where the product may have been exposed, the safest assumption is that the secret is no longer trustworthy. Reset or replace any credential material tied to the affected function, review adjacent accounts and integrations that may have inherited the same trust path, and retain logs that help establish whether the system was accessed before the fix was applied.

Risk and Threat Considerations

This vulnerability matters because hard-coded credentials create a repeatable entry point: once one copy of the default key is known, any instance that still trusts it can be accessed in the same way. The risk is highest where the product sits near monitoring, administration, or other privileged functions, because successful access can expose configuration data, operational visibility, or downstream systems that trust the same secret.

Failure mechanism: An attacker or other unauthorised actor uses the embedded API key as a valid credential, bypassing normal user authentication and gaining access through a trust path that defenders may not notice quickly.

Impact: The result can be unauthorised access, configuration tampering, loss of monitoring integrity, and possible lateral exposure if the same credential is accepted by linked systems or automation.

Practitioner Guidance

What to verify: Confirm whether the instance is on the affected product path, whether the default key is still present, and whether any dependent process relies on that key for routine operation. If the key is present in code, config, or deployed images, assume it must be rotated or removed everywhere it appears.

Decision rule: If you cannot prove that the embedded credential was never exposed, treat it as compromised and prioritise replacement over prolonged forensic debate. If patching or reconfiguration must wait, isolate the system and limit access to the smallest viable administrative path until the secret is replaced.

Practitioner takeaway: With hard-coded credentials, the main question is not whether exploitation is possible, but whether you can still trust any system that accepted the shared secret before remediation.

Related resources from NHI Mgmt Group

• Guide: Zero-Day and Exploited Vulnerabilities Guide
• CVE-2020-8657 (EyesOfNetwork Use of Hard-Coded Credentials)
• Is CVE-2026-20316 (Cisco Secure Firewall Management Center Use of Hard-coded Password) being exploited in the wild?
• CVE-2020-29583 (Zyxel Multiple Products Use of Hard-Coded Credentials)
• What is the impact of using hard-coded credentials on security?