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CVE-2026-75491 Cudy TR3000 before 2.5.42 MQTT JWT Authentication Bypass via alg none Tokens

9.2 criticalEPSS 0.2%

Critical (9.2) in shenzhen cudy technology co., ltd. tr3000 1.0. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.

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Cudy TR3000 before 2.5.42 contains an authentication bypass vulnerability in the Mosquitto plugin auth_plugin_jwt.so that accepts unsigned JWTs using alg none. Attackers holding any Cudy-trusted client certificate can authenticate as admincudydevice on port 8883 and publish batchcmd requests to execute commands as root.

Severity

CVSS 4.0

9.2 critical
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CVSS 3.1

8.1 high
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.2% estimated probability of exploitation activity in the next 30 days; 16th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CWE
CWE-347 Improper Verification of Cryptographic Signature
OWASP Top 10
A04:2025 Cryptographic Failures
Published
Assigned by
VulnCheck (CNA)
NVD analysis
Awaiting analysis
Record from
the NVD, synced

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Affected

  • shenzhen cudy technology co., ltd.:tr3000 1.0

Versions

From the CNA's record in the CVE List.

ProductAffected
Shenzhen Cudy Technology Co., Ltd. TR3000 1.0before 2.5.42

Attack patterns (CAPEC)

  • CAPEC-463 Padding Oracle Crypto Attack Severity: High
  • CAPEC-475 Signature Spoofing by Improper Validation Likelihood: Low · Severity: High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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