PatchTheCVECVE-2021-20137: A reflected cross-site scripting vulnerability exists in the url parameter of the /cgi-bin/luci/site_access/ p
CVE-2021-20137 is a medium-severity flaw (CVSS 6.1) affecting gryphon tower firmware. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
A reflected cross-site scripting vulnerability exists in the url parameter of the /cgi-bin/luci/site_access/ page on the Gryphon Tower router's web interface. An attacker could exploit this issue by tricking a user into following a specially crafted link, granting the attacker javascript execution in the context of the victim's browser.
Why this priority
- Public exploit reference
A fixed release or distro patch exists.
Risk facts
| CVSS score | 6.1 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | Required |
| EPSS exploit chance | 2.3% (top 17%) |
| CISA exploited list | No |
| Weakness | CWE-79 |
| Published | 2021-12-09 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Public exploits and detection
Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.
- Nuclei scan template: Gryphon Tower - Cross-Site Scripting
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2021-20137?
gryphon tower firmware: upgrade to newer than 04.0004.12. Exact commands for each OS are on this page.
Is CVE-2021-20137 being exploited?
CVE-2021-20137 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2021-20137 affect?
CVE-2021-20137 affects gryphon tower firmware. Severity is medium (CVSS 6.1). A reflected cross-site scripting vulnerability exists in the url parameter of the /cgi-bin/luci/site_access/ page on the Gryphon Tower router's web interface. An attacker could exploit this issue by tricking a user into following a speciall
How urgent is CVE-2021-20137?
Priority 47/100. Public exploit reference
Related CVEs
- CVE-2021-20146 CRITICAL 9.8 UPGRADE An unprotected ssh private key exists on the Gryphon devices which could be used to achieve root access to a s
- CVE-2021-20145 HIGH 7.5 UPGRADE Gryphon Tower routers contain an unprotected openvpn configuration file which can grant attackers access to th
- CVE-2021-20144 HIGH 8.8 UPGRADE An unauthenticated command injection vulnerability exists in the parameters of operation 49 in the controller_
- CVE-2021-20143 HIGH 8.8 UPGRADE An unauthenticated command injection vulnerability exists in the parameters of operation 48 in the controller_
- CVE-2021-20142 HIGH 8.8 UPGRADE An unauthenticated command injection vulnerability exists in the parameters of operation 41 in the controller_