Cyber Resilience

CVE-2019-25603

HighPublic PoC

Published: 22 March 2026

Published
22 March 2026
Modified
16 April 2026
KEV Added
Patch
CVSS Score v4 8.6 CVSS:4.0/AV:L/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
EPSS Score 0.0019 8.2th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2019-25603 is a high-severity Out-of-bounds Write (CWE-787) vulnerability in Tuneclone (inferred from references). Its CVSS base score is 8.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked at the 8.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).

Deeper analysis

CVE-2019-25603 is a structured exception handler (SEH) buffer overflow vulnerability in TuneClone version 2.20. The flaw occurs when processing a malicious license code string entered into the application's license code field, leading to a buffer overflow that overwrites the SEH.

Local attackers can exploit this vulnerability without privileges by crafting a payload consisting of a controlled buffer, an NSEH jump instruction, and an SEH handler address pointing to a ROP gadget. Pasting this payload into the license code field triggers the overflow, enabling arbitrary code execution, such as establishing a bind shell. The CVSS v3.1 base score is 8.4 (AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), reflecting high impact on confidentiality, integrity, and availability for unauthenticated local users.

Advisories and exploit details are documented by Vulncheck at https://www.vulncheck.com/advisories/tuneclone-structured-exception-handler-buffer-overflow and Exploit-DB at https://www.exploit-db.com/exploits/47012. The vendor site is http://www.tuneclone.com/, with the affected setup executable available at http://www.tuneclone.com/tuneclone_setup.exe. No patch or mitigation guidance is specified in the CVE details.

EU & UK References

Vulnerability details

TuneClone 2.20 contains a structured exception handler (SEH) buffer overflow vulnerability that allows local attackers to execute arbitrary code by supplying a malicious license code string. Attackers can craft a payload with a controlled buffer, NSEH jump instruction, and SEH…

more

handler address pointing to a ROP gadget, then paste it into the license code field to trigger code execution and establish a bind shell.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
Why these techniques?

Local SEH buffer overflow in client application directly enables arbitrary code execution via crafted input.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2019-25705Shared CWE-787
CVE-2019-25633Shared CWE-787
CVE-2026-0538Shared CWE-787
CVE-2016-20046Shared CWE-787
CVE-2019-25628Shared CWE-787
CVE-2019-25695Shared CWE-787
CVE-2018-25218Shared CWE-787
CVE-2026-42484Shared CWE-787
CVE-2019-25612Shared CWE-787
CVE-2025-43300Shared CWE-787

Affected Assets

Tuneclone
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Requires validation of untrusted inputs like the license code string to detect and reject malformed or oversized data that triggers the SEH buffer overflow.

prevent

Implements memory protection mechanisms such as DEP and ASLR to prevent exploitation of the buffer overflow via ROP gadgets and arbitrary code execution.

prevent

Restricts the length and format of inputs to the license code field to limit buffer overflow opportunities from excessively long malicious strings.

References