Remote code execution via compounded buffer overflows
Published May 27, 2026 · Updated May 27, 2026
Stack-based buffer overflow in Tasmota 15.3.0.3 and earlier allows remote attackers to execute arbitrary code through fetch_jpg(). The function copies an unbounded multipart boundary into a 40-byte buffer and stores oversized frame lengths in 16 bits, producing undersized allocations and compounded memory corruption. Exploitation requires an ESP32 build with scripter and streaming JPEG support, plus a script that fetches an attacker-controlled or intercepted MJPEG stream.
Summary
What happened
Stack-based buffer overflow in Tasmota 15.3.0.3 and earlier allows remote attackers to execute arbitrary code through fetch_jpg(). The function copies an unbounded multipart boundary into a 40-byte buffer and stores oversized frame lengths in 16 bits, producing undersized allocations and compounded memory corruption. Exploitation requires an ESP32 build with scripter and streaming JPEG support, plus a script that fetches an attacker-controlled or intercepted MJPEG stream.
The record
- CVE
- CVE-2026-38422
- Published
- May 27, 2026
- Updated
- May 27, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-121, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 27, 2026CVE publishedPublication date reported by the CVE source.
- May 27, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Combined buffer-overflow proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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