Buffer overflow in Mersenne Prime95
CVE-2018-25299
Prime95 29.4b8 contains a local buffer overflow vulnerability that allows attackers to execute arbitrary code by exploiting structured exception handling (SEH) mechanisms. Attackers can inject malicious payload through the optional proxy hostname field in the PrimeNet connection settings to trigger the overflow and execute system commands.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.4 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.002 (4.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 5th percentile — 4.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Mersenne Prime95 — versions 29.4b8
Weakness classification (CWE)
References
- www.exploit-db.com/exploits/44649 (exploit)
- www.mersenne.org/ (product)
- www.mersenne.org/download/ (product)
- www.vulncheck.com/advisories/prime95-29-4b8-local-buffer-overflow-via-seh (third-party-advisory)
Frequently asked questions
- What is CVE-2018-25299?
- CVE-2018-25299 is a high-severity vulnerability in Mersenne Prime95, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 8.4/10. Published 2026-04-29.
- How severe is CVE-2018-25299?
- High severity. CVSS v3 base score is 8.4 out of 10.