πŸ” CVE Alert

CVE-2026-73673

HIGH 8.8

Netis NC63 V3.0.0.3327 Unauthenticated Firmware Update with Missing Cryptographic Firmware Authentication

CVSS Score
8.8
EPSS Score
0.0%
EPSS Percentile
0th

Netis NC63 router firmware V3.0.0.3327 contains an unauthenticated firmware update vulnerability that allows unauthenticated attackers to submit unsigned firmware images by exploiting a missing authentication enforcement flaw in the Boa web server and netis.cgi CGI dispatcher. Attackers can send a multipart POST request to /cgi-bin/upload_fw.cgi without a valid session cookie, bypassing authentication because Boa grants access to any path containing '.cgi' regardless of cookie validation, and netis.cgi reads but does not enforce the authentication state before invoking the firmware update handler, which accepts images validated only by a forgeable additive checksum and static product strings rather than a cryptographic signature, potentially enabling persistent router compromise.

CWE CWE-306
Vendor netis systems co., ltd.
Product netis nc63 wireless ac1200 router
Published Aug 14, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector
Adjacent
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Affected Versions

Netis Systems Co., Ltd. / Netis NC63 Wireless AC1200 Router
0 ≀ V3.0.0.3327

References

NVD β†— CVE.org β†— EPSS Data β†—
netis-systems.com: https://www.netis-systems.com/detail/proid/307/NC63.html ozcanpng.dev: https://ozcanpng.dev/blog/cve-2026-73673-netis-nc63-unauthenticated-firmware-update/ github.com: https://github.com/ozcanpng/CVE-2026-73673 vulncheck.com: https://www.vulncheck.com/advisories/netis-nc63-unauthenticated-firmware-update-with-missing-cryptographic-firmware-authentication

Credits

πŸ” Γ–zcan Ersan (@ozcanpng)