CVE-2026-119756 (GCVE-0-2026-119756)
Vulnerability from cvelistv5 – Published: 2026-11-09 17:28 – Updated: 2026-11-09 22:51 X_Open Source
VLAI
EPSS
VEX
Title
Tasmota 16.0.0 Heap Out-of-Bounds Write via Device Groups UDP
Summary
Tasmota through 16.0.0, fixed in commit e97e1e4, contains a heap out-of-bounds write vulnerability in SendReceiveDeviceGroupMessage() that allows unauthenticated attackers on the local network to corrupt heap memory by sending crafted Device Groups messages over UDP port 4447 that cause the log_remaining counter to go negative and writes to exceed the fixed 512-byte buffer. Attackers can exploit this flaw to crash the device or potentially achieve native code execution on ESP8266 and ESP32 platforms that lack ASLR and heap cookies.
Severity
9.8 (Critical)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-09 22:51 UTC
CWE
- CWE-805 - Buffer Access with Incorrect Length Value
Assigner
VulnCheck
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/arendst/Tasmota/commit/e97e1e4… | patchissue-tracking |
| https://www.vulncheck.com/advisories/tasmota-heap… | third-party-advisory |
Impacted products
Date Public
2026-11-06 00:00
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