What’s Vulnerable › Vulnerabilities

CVE-2021-45939

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.9% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2022-01-01 · updated 2026-06-17
• Weakness: CWE-787

Description

wolfSSL wolfMQTT 1.9 has a heap-based buffer overflow in MqttClient_DecodePacket (called from MqttClient_WaitType and MqttClient_Subscribe).

Affected products

• wolfSSL Wolfmqtt: 1.9

References

• https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=39103
• https://github.com/google/oss-fuzz-vulns/blob/main/vulns/wolfmqtt/OSV-2021-1361.yaml
• https://github.com/wolfSSL/wolfMQTT/commit/84d4b53122e0fa0280c7872350b89d5777dabbb2
• https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=39103
• https://github.com/google/oss-fuzz-vulns/blob/main/vulns/wolfmqtt/OSV-2021-1361.yaml
• https://github.com/wolfSSL/wolfMQTT/commit/84d4b53122e0fa0280c7872350b89d5777dabbb2

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