CVE-2017-5521
Published: 17 January 2017
Summary
CVE-2017-5521 is a high-severity an unspecified weakness vulnerability in Netgear R6200 Firmware. Its CVSS base score is 8.1 (High).
Operationally, ranked in the top 0.1% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 AC-17 (Remote Access) and AC-3 (Access Enforcement).
Deeper analysis
CVE-2017-5521 affects the web management interface on multiple NETGEAR router models including the R8500, R8300, R7000, R6400, R7300, R7100LG, R6300v2, WNDR3400v3, WNR3500Lv2, R6250, R6700, R6900, and R8000. The flaw permits password disclosure through specially crafted requests to the management server, exposing the administrator credentials when certain recovery conditions are not met.
An attacker can exploit the issue remotely over the internet if remote management is enabled, or from within the LAN or WLAN. After canceling an authentication prompt and obtaining a recovery token, the attacker supplies it to the endpoint /passwordrecovered.cgi?id=TOKEN; if password recovery has never been enabled, the device returns the admin password. The exposure persists even after recovery is later disabled because the router continues to enforce prior security-question checks.
NETGEAR advisory KB30632 and related disclosures at SecurityFocus address the vulnerability, while a working proof-of-concept is publicly available on Exploit-DB. The CVSS 8.1 score reflects high impact on confidentiality, integrity, and availability under network attack conditions.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2017-14625
Vulnerability details
An issue was discovered on NETGEAR R8500, R8300, R7000, R6400, R7300, R7100LG, R6300v2, WNDR3400v3, WNR3500Lv2, R6250, R6700, R6900, and R8000 devices. They are prone to password disclosure via simple crafted requests to the web management server. The bug is exploitable…
more
remotely if the remote management option is set, and can also be exploited given access to the router over LAN or WLAN. When trying to access the web panel, a user is asked to authenticate; if the authentication is canceled and password recovery is not enabled, the user is redirected to a page that exposes a password recovery token. If a user supplies the correct token to the page /passwordrecovered.cgi?id=TOKEN (and password recovery is not enabled), they will receive the admin password for the router. If password recovery is set the exploit will fail, as it will ask the user for the recovery questions that were previously set when enabling that feature. This is persistent (even after disabling the recovery option, the exploit will fail) because the router will ask for the security questions.
- CWE(s)
- KEV Date Added
- 08 September 2022
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly enforces authentication and authorization checks before allowing access to sensitive endpoints such as /passwordrecovered.cgi, blocking the unauthenticated token-based password disclosure.
Requires explicit authorization, encryption, and monitoring of remote management connections, eliminating the remote attack vector when remote management is enabled on the affected routers.
Mandates secure generation, storage, and recovery procedures for authenticators, preventing exposure of the admin password via improperly implemented recovery tokens.