CVE-2026-75491: Shenzhen Cudy Technology TR3000 1.0 · Improper Verification of Cryptographic Signature
Affects Shenzhen Cudy Technology TR3000 1.0Source CVE Database V5
Not known to be exploited · CVSS 9.2 Critical : upgrade to 2.5.42 as a priority.
Data as of 13 Nov 2026, 10:31 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 9.2 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 8.1 |
- Patch
- Available – fixed in 2.5.42
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 13 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Upgrade Shenzhen Cudy Technology TR3000 1.0 to 2.5.42.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Shenzhen Cudy Technology Co., Ltd.TR3000 1.0 | Affected
| Fixed in
|
AI-suggested
Upgrade affected devices to version 2.5.42 or later, where the vulnerability is fixed. No other mitigations are indicated. Since this is a device firmware vulnerability, patching is the primary remediation.
Description
CVE-2026-75491 is an authentication bypass vulnerability in Shenzhen Cudy Technology Co., Ltd.'s TR3000 device versions before 2.5.42. The flaw exists in the Mosquitto plugin auth_plugin_jwt.so, which improperly accepts unsigned JWT tokens using the 'alg none' algorithm. This allows attackers possessing any Cudy-trusted client certificate to authenticate as the admincudydevice user on port 8883 and execute commands as root via batchcmd requests.
References
- cudy.com/en-us/pages/download-center/tr3000-1-0 (opens in a new tab)
- d1jvyy13vm72kv.cloudfront.net/device/upgrade/m_upgrade_TR3000_256MB_Flash-R103-2.5.42-20261103-160202-sysupgrade_82672.zip (opens in a new tab)
- vulncheck.com/advisories/cudy-tr3000-before-2.5.42-mqtt-jwt-authentication-bypass-via-alg-none-tokens (opens in a new tab)