arendst Tasmota up to 16.0.0 SendReceiveDeviceGroupMessage out-of-bounds write

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.6$0-$5k0.00+

Summaryinfo

A vulnerability was found in arendst Tasmota up to 16.0.0. It has been declared as very critical. The affected element is the function SendReceiveDeviceGroupMessage. Such manipulation leads to out-of-bounds write. This vulnerability is listed as CVE-2026-119756. The attack may be performed from remote. There is no available exploit. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability, which was classified as very critical, has been found in arendst Tasmota up to 16.0.0. Affected by this issue is the function SendReceiveDeviceGroupMessage. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-119756 since 10/30/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 11/09/2026).

Applying the patch e97e1e4f7e319a55caa1613aef1f25fc81bdb554 is able to eliminate this problem.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.6

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: e97e1e4f7e319a55caa1613aef1f25fc81bdb554

Timelineinfo

10/30/2026 CVE reserved
11/09/2026 +10 days Advisory disclosed
11/09/2026 +0 days VulDB entry created
11/09/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CNA: VulnCheck
CVE: CVE-2026-119756 (🔒)

GCVE (CVE): GCVE-0-2026-119756
GCVE (VulDB): GCVE-100-433208

Entryinfo

Created: 11/09/2026 18:50
Changes: 11/09/2026 18:50 (76)
Complete: 🔍
Cache ID: 216::103

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