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No exploitation reportedAwaiting NVD analysis

CVE-2026-119756

Tasmota 16.0.0 Heap Out-of-Bounds Write via Device Groups UDP

No exploitation reported by the sources we read.

  • Published2026-11-09
  • WeaknessCWE-805

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

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.

Timeline

dates in UTC
  1. 2026-11-0917:28CVE publishedCNA

Versions per branch

Products declared by the CNA

As VulnCheck, the CNA that assigned this CVE, declared them in the CVE record; versions as written. NVD lists no product for this CVE yet: this is the only product data so far.

Source: the CNA record (CVE Program), © The MITRE Corporation,CVE Terms of UseCVE recordupdated 2026-11-09

Neither OSV.dev nor the vendor advisories we read list affected versions for CVE-2026-119756 yet.

Full record on NVD

Fix

No fix published by the sources we read yet. NVD record

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Metasploit modules
none listed
Metasploit Framework

Sources

  • CISA-ADPSSVC decisionnone2026-11-09
  • CNACVSS 4.09.32026-11-09
  • CNACVSS 3.19.82026-11-09
  • NVDCVSS 3.19.8read 2026-11-09
  • CNAweakness (CWE)CWE-8052026-11-09
  • NVDweakness (CWE)CWE-805read 2026-11-09
  • GitHub Advisoriesadvisory—

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 4.0 vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Published
2026-11-09
Last Modified
2026-11-09
NVD status
Received
GitHub Advisory
GHSA-6g2f-6p9p-vvm8

Frequently asked questions

What is CVE-2026-119756?

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.

Is CVE-2026-119756 actively exploited?

Active exploitation of CVE-2026-119756 has not been confirmed.

What is the CVSS score for CVE-2026-119756?

CVE-2026-119756 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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