CVE-2026-32696
NanoMQ HTTP Auth: Missing username/password can trigger a NULL-pointer strlen() in auth_http.c:set_data(), causing a process crash — SIGSEGV, remotely triggerable
NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In NanoMQ version 0.24.6, after enabling auth.http_auth (HTTP authentication), when a client connects to the broker using MQTT CONNECT without providing username/password, and the configuration params uses the placeholders %u / %P (e.g., username="%u", password="%P"), the HTTP request construction phase enters auth_http.c:set_data(). This results in calling strlen() on a NULL pointer, causing a SIGSEGV crash. This crash can be triggered remotely, resulting in a denial of service. This issue has been patched in version 0.24.7.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
3.1
NanoMQ HTTP Auth: Missing username/password can trigger a NULL-pointer strlen() in auth_http.c:set_data(), causing a process crash — SIGSEGV, remotely triggerable
NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In NanoMQ version 0.24.6, after enabling auth.http_auth (HTTP authentication), when a client connects to the broker using MQTT CONNECT without providing username/password, and the configuration params uses the placeholders %u / %P (e.g., username="%u", password="%P"), the HTTP request construction phase enters auth_http.c:set_data(). This results in calling strlen() on a NULL pointer, causing a SIGSEGV crash. This crash can be triggered remotely, resulting in a denial of service. This issue has been patched in version 0.24.7.
- Record
CVE-2026-32696- CVSS 3.1
- 3.1 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L - Weakness
- CWE-476
- Updated
- 2026-11-02
EUVDEUVD-2026-17209
3.1
NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In NanoMQ version 0.24.6, after enabling auth.http_auth (HTTP authentication), when a client connects to the broker using MQTT CONNECT without providing username/password, and the configuration params uses the placeholders %u / %P (e.g., username="%u", password="%P"), the HTTP request construction phase enters auth_http.c:set_data(). This results in calling strlen() on a NULL pointer, causing a SIGSEGV crash. This crash can be triggered remotely, resulting in a denial of service. This issue has been patched in version 0.24.7.
- Record
EUVD-2026-17209- CVSS 3.1
- 3.1 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
NVD
3.1
NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In NanoMQ version 0.24.6, after enabling auth.http_auth (HTTP authentication), when a client connects to the broker using MQTT CONNECT without providing username/password, and the configuration params uses the placeholders %u / %P (e.g., username="%u", password="%P"), the HTTP request construction phase enters auth_http.c:set_data(). This results in calling strlen() on a NULL pointer, causing a SIGSEGV crash. This crash can be triggered remotely, resulting in a denial of service. This issue has been patched in version 0.24.7.
- Record
CVE-2026-32696- CVSS 3.1
- 3.1 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
OSV
3.1
NanoMQ HTTP Auth: Missing username/password can trigger a NULL-pointer strlen() in auth_http.c:set_data(), causing a process crash — SIGSEGV, remotely triggerable
NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In NanoMQ version 0.24.6, after enabling auth.http_auth (HTTP authentication), when a client connects to the broker using MQTT CONNECT without providing username/password, and the configuration params uses the placeholders %u / %P (e.g., username="%u", password="%P"), the HTTP request construction phase enters auth_http.c:set_data(). This results in calling strlen() on a NULL pointer, causing a SIGSEGV crash. This crash can be triggered remotely, resulting in a denial of service. This issue has been patched in version 0.24.7.
- Record
CVE-2026-32696- CVSS 3.1
- 3.1 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L - Weakness
- CWE-476
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-32696 is a low vulnerability (CVSS 3.1) in Emqx Nanomq, published March 30, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.41%, the 36th percentile. No source names a fixed version.
References
github.com/nanomq/nanomq/security/advisories/GHSA-77f4-wvq8-mp3p
github.com/nanomq/NanoNNG/pull/1394
github.com/nanomq/NanoNNG/commit/c20aa27e5290bb480a5315099952480d35f37a8b
github.com/nanomq/nanomq/releases/tag/0.24.7
github.com/CVEProject/cvelistV5/tree/main/cves/2026/32xxx/CVE-2026-32696.json
nvd.nist.gov/vuln/detail/CVE-2026-32696