Use After Free in Monkey-Project Monkey
CVE-2025-63651
A use-after-free in the mk_string_char_search function (mk_core/mk_string.c) of monkey commit f37e984 allows attackers to cause a Denial of Service (DoS) via sending a crafted HTTP request to the server.
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.011 (62.9th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 63rd percentile — 62.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.009 · newest: 0.011 · change: +0.001
Affected products
Weakness classification (CWE)
References
- github.com/monkey/monkey/issues/426 (Exploit, Issue Tracking)
- github.com/archersec/security-advisories/blob/master/monkey/monkey-advisory-202… (Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2025-63651?
- CVE-2025-63651 is a high-severity vulnerability in Monkey-Project Monkey, classified under Use After Free. CVSS score: 7.5/10. Published 2026-01-29.
- How severe is CVE-2025-63651?
- High severity. CVSS v3 base score is 7.5 out of 10.