Buffer overflow in Mersenne Prime95

CVE-2018-25293

Prime95 29.4b7 contains a buffer overflow vulnerability in the PrimeNet connection dialog that allows local attackers to crash the application by supplying an excessively long string in the optional proxy password field. Attackers can trigger a denial of service by entering a 6000-byte payload into the proxy password parameter, causing the application to crash when processing the connection settings.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.2 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.001 (2.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 3rd percentile — 2.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2018-25293: held from 0.001 to 0.001.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2018-25293?
CVE-2018-25293 is a medium-severity vulnerability in Mersenne Prime95, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 6.2/10. Published 2026-04-26.
How severe is CVE-2018-25293?
Medium severity. CVSS v3 base score is 6.2 out of 10.