Echo Mirage 3.1 contains a stack buffer overflow that allows a local attacker to crash the application or execute arbitrary code by supplying an oversized string in the Rules action field. The flaw permits overwriting a return address, enabling the attacker to run malicious code under the application's privileges. This vulnerability is classified as CWE‑787, a typical stack‑based buffer overflow, and can lead to full compromise of the machine on which Echo Mirage runs.

The affected product is Echo Mirage 3.1 from Sourceforge. All installations of this version are vulnerable, as the CNA data does not restrict the vulnerability to a narrower set of releases. Any system running Echo Mirage 3.1 and allowing local users to interact with the Rules dialog is at risk.

The CVSS score of 8.6 indicates a high severity vulnerability. No EPSS score is available and the issue is not listed in the CISA KEV catalog, but the exploitation only requires local access. The likely attack vector is a local user who can create a malicious text file, copy its contents into the Rules action field via the dialog, and trigger the buffer overflow to overwrite the return address. Once the overflow executes, the attacker gains control over the application process and potentially the entire system.