CVE-2026-38427
HighCVSS 7.3Exploitation Probability (EPSS)
Low risk36th percentile - higher than 36% of all known CVEs
Summary
Tasmota versions up to 15.3.0.3 contain an issue in the fetch_jpg() function that allows a remote attacker to cause a heap buffer overflow. The Content-Length from a JPEG stream is stored in a uint16_t variable, leading to allocation of a smaller buffer than the data actually read when the value exceeds 65535.
Risk Assessment
An attacker could exploit this vulnerability to execute malicious code or destabilize the system, potentially leading to serious security implications for the organization.
Recommendation
It is recommended to update Tasmota to the latest version to mitigate this vulnerability and to monitor systems for unauthorized activities.
Other vulnerabilities in Tasmota
See all- CVE-2026-119755High
Tasmota through 16.0.0 (fixed in commit 1cb7ebc) contains a cross-site request forgery vulnerability that allows unauthenticated attackers to bypass Referer-based CSRF protection in HttpCheckPriviledgedAccess() by crafting a Referer header where the device hostname or IP appears as a substring immediately after http://evil.com/. Attackers can lure an administrator on the device's network to a malicious page to issue arbitrary console commands and reconfigure Wi-Fi, MQTT, settings, or firmware on devices lacking a WebPassword.
- CVE-2026-119756Critical
Tasmota through 16.0.0 (fixed in commit e97e1e4) contains a heap out-of-bounds write in SendReceiveDeviceGroupMessage() that allows unauthenticated attackers on the local network to corrupt heap memory by sending crafted Device Groups messages over UDP port 4447. The messages cause the log_remaining counter to go negative and writes to exceed the fixed 512-byte buffer. This can crash the device or potentially achieve native code execution on ESP8266 and ESP32 platforms lacking ASLR and heap cookies.
Original NVD description (English source)
An issue in fetch_jpg() in xdrv_10_scripter.ino in Tasmota through 15.3.0.3 allows a remote attacker to cause heap buffer overflow. The Content-Length from a JPEG stream is stored in a uint16_t variable; values above 65535 wrap around, causing allocation of a smaller buffer than the data actually read.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS