Buffer overflow in Echatserver Easy Chat Server
CVE-2018-25221
EChat Server 3.1 contains a buffer overflow vulnerability in the chat.ghp endpoint that allows remote attackers to execute arbitrary code by supplying an oversized username parameter. Attackers can send a GET request to chat.ghp with a malicious username value containing shellcode and ROP gadgets to achieve code execution in the application context.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.008 (55.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 55.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000
Affected products
- Echatserver Easy Chat Server
- Echatserver Echat Server — versions 3.1
Weakness classification (CWE)
References
- www.exploit-db.com/exploits/44155 (Exploit, exploit)
- www.vulncheck.com/advisories/echat-server-buffer-overflow-via-chat-ghp-username… (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2018-25221?
- CVE-2018-25221 is a critical-severity vulnerability in Echatserver Easy Chat Server, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-03-28.
- How severe is CVE-2018-25221?
- Critical severity. CVSS v3 base score is 9.8 out of 10.