CVE-2020-8657 is an use of hard-coded credentials vulnerability in EyesOfNetwork EyesOfNetwork. CISA added it to the Known Exploited Vulnerabilities catalogue on 3 November 2021, which means attackers have used it in real attacks. EyesOfNetwork contains a use of hard-coded credentials vulnerability, as it uses the same API key by default.
What hard-coded credentials mean in a CVE context
A hard-coded credential vulnerability means the product ships with an embedded secret, such as an API key or password, that is reused by design rather than set uniquely for each deployment. That creates a predictable authentication path that attackers can test once and then reuse wherever the same secret exists.
In a web or API-enabled product, the damage is not limited to login bypass. A reused embedded key can expose administrative functions, internal data, configuration endpoints, or privileged integrations, especially when the secret is treated as trusted by default across instances.
Why this flaw is dangerous in EyesOfNetwork
For EyesOfNetwork, the key danger is that the vulnerable secret is the same by default, so the weakness is not just misconfiguration by a single operator. Every exposed or reachable deployment may inherit the same trust failure until the embedded credential is removed or replaced.
This matters because hard-coded credentials are easy to discover through reverse engineering, source review, traffic inspection, or simple reuse across installations. Once discovered, they can turn a monitoring or management platform into a foothold for unauthorized access, persistence, or lateral movement.
When tracking product-specific exposure, readers should rely on the vendor advisory and the CVE Program record structure, and on the NIST National Vulnerability Database for vulnerability metadata and reference data.
How organisations check exposure and reduce attack surface
The first question is whether any EyesOfNetwork instance is in the asset inventory, where it is deployed, and whether it is reachable from the internet or from networks an attacker could reach after initial compromise. Exposure is often determined by placement and access paths as much as by the software flaw itself.
Teams should then compare deployment details with the vendor advisory and confirm whether they have removed the default or embedded key, rotated any related API credentials, and isolated the affected service from broader trust relationships. If the platform is tied into other systems, that linkage can magnify the blast radius of a single reused secret.
Broader credential hygiene also applies. NHIMG’s API Key Management Guide and Secrets Management Guide are useful when the core issue is whether an embedded secret has been scoped, stored, rotated, and revoked safely.
Remediation, detection, and post-exploitation review
Remediation should focus on replacing any hard-coded secret with a unique deployment-specific credential, then revoking the old value everywhere it may have been copied or cached. If a patch cannot be applied immediately, organisations should restrict access to the vulnerable service, block unnecessary inbound paths, and remove any network exposure that is not operationally required.
Detection should look for unexpected use of the embedded API key, unusual administrative actions, new accounts, configuration changes, or access from unfamiliar source addresses. After patching, review logs for signs that the credential was already used before remediation, because fixing the software does not erase prior compromise.
If exploitation is suspected, any downstream secrets, sessions, or privileged tokens that the attacker could have reached through EyesOfNetwork should be reviewed and rotated. The practical question is not only whether the vulnerable key was changed, but whether it enabled broader trust abuse before it was removed.
Risk and Threat Considerations
Hard-coded credentials are especially dangerous because they collapse authentication into a reusable secret that is often discoverable outside normal operational controls. Once that secret is known, an attacker may gain the same trusted access as the legitimate application or operator account that was meant to use it.
Failure mechanism: The embedded API key can be extracted from the product or guessed from known defaults, then reused to authenticate directly or pivot into functions that assume the caller is trusted.
Impact: The result can be unauthorized access, privilege abuse, data exposure, persistence in the management plane, and possible reuse of the same trust relationship across multiple deployments.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10 and OWASP API Security Top 10 address the attack and risk surface, while NIST SP 800-53 Rev 5 sets the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-02 — Secret Leakage | Hard-coded API keys are embedded secrets that can be exposed and reused. |
| NHI-07 — Long-Lived Secrets | A default shared API key is a long-lived credential that resists safe rotation. | |
| NHI-05 — Overprivileged NHI | A reused default API key often grants broader access than the deployment needs. | |
| Recommendation — Eliminate embedded secrets and rotate any exposed keys immediately. Replace long-lived shared credentials with uniquely issued, short-lived secrets. Scope the credential to the minimum permissions required by the service. | ||
| NIST SP 800-53 Rev 5 | IA-5 — Authenticator Management | Covers the lifecycle of authenticators, including issuance, rotation, revocation and protection. |
| AC-6 — Least Privilege | A default API key should not retain broad rights after deployment. | |
| Recommendation — Manage the API key lifecycle so exposed authenticators are revoked and replaced promptly. Reduce the key's permissions to the minimum access needed for the function. | ||
| OWASP API Security Top 10 | API2 — Broken Authentication | A shared embedded API key weakens authentication and enables unauthorized use. |
| Recommendation — Remove shared credentials and verify that authentication cannot be replayed with a default key. | ||
Practitioner Guidance
Why practitioners should care: Treat every embedded secret as a lifecycle failure, not just a software bug. If the same credential is present in more than one deployment, one compromise can become many compromises, especially in management or monitoring platforms that sit close to high-value systems.
What to watch for: Prioritise any deployment where the product documentation, vendor advisory, or internal review indicates a default or shared API key. In those cases, the operational question is whether the secret can be replaced cleanly without breaking integrations or leaving stale trust paths behind.
Related resources from NHI Mgmt Group
- What happens when DevOps teams use hard-coded or long-lived credentials instead of just-in-time access?
- CVE-2026-20316 (Cisco Secure Firewall Management Center Use of Hard-coded Password)
- What is the impact of using hard-coded credentials on security?
- What breaks when MCP credentials are hard coded?