Cyber Resilience

CVE-2018-25221

Memory Safety in Echatserver Easy Chat Server ≤ 3.1

Public PoCMemory Safety
Published
28 March 2026
Modified
02 April 2026
CVSS Score v4 9.3
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0082 54th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2018-25221 is a critical-severity Out-of-bounds Write (CWE-787) vulnerability in Echatserver Easy Chat Server. Its CVSS base score is 9.3 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 46% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and SI-16 (Memory Protection) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2018-25221 is a buffer overflow vulnerability (CWE-787) in EChat Server 3.1, specifically affecting the chat.ghp endpoint. The issue arises from processing an oversized username parameter, which can trigger a buffer overflow. Published on 2026-03-28, it carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating critical severity due to its potential for high-impact remote exploitation.

Remote, unauthenticated attackers can exploit this vulnerability by sending a GET request to the chat.ghp endpoint with a malicious username parameter containing shellcode and ROP gadgets. Successful exploitation leads to arbitrary code execution in the context of the affected application.

Advisories and related resources include a Vulncheck advisory detailing the buffer overflow via the chat.ghp username parameter and a public exploit published on Exploit-DB at https://www.exploit-db.com/exploits/44155. No specific patch or mitigation details are outlined in the provided information.

EU & UK References

Vulnerability Data

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…

more

shellcode and ROP gadgets to achieve code execution in the application context.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

CVE-2018-25221 is a buffer overflow in a public-facing chat server endpoint (chat.ghp) allowing unauthenticated remote code execution via crafted GET request, directly mapping to Exploit Public-Facing Application.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2024-12248Shared CWE-787
CVE-2024-41461Shared CWE-787
CVE-2025-25897Shared CWE-787
CVE-2025-29385Shared CWE-787
CVE-2023-49043Shared CWE-787
CVE-2025-25744Shared CWE-787
CVE-2024-57579Shared CWE-787
CVE-2025-25742Shared CWE-787
CVE-2024-57582Shared CWE-787
CVE-2023-49044Shared CWE-787

Affected Assets

echatserver
easy chat server
≤ 3.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-10 Information Input Validation
  • SI-16 Memory Protection
  • SI-2 Flaw Remediation
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Requires validation of the oversized username parameter in the chat.ghp GET request to prevent buffer overflow exploitation.

prevent

Implements memory safeguards like DEP and ASLR to block execution of shellcode and ROP gadgets from the buffer overflow.

prevent

Directs identification, reporting, and patching of the specific buffer overflow flaw in EChat Server's chat.ghp endpoint.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure-development practices (static analysis, bounds checking, code review) are the primary means of preventing out-of-bounds writes.

ID.RA-01 partial match
prevents

Vulnerability scanning and recording can discover out-of-bounds write flaws so they can be remediated.

PR.PS-02 partial match
prevents

Patching or replacing vulnerable software directly eliminates known instances of this coding weakness.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing in development and acceptance can detect and prevent out-of-bounds write defects.

prevents

Secure development life cycle mandates practices that prevent out-of-bounds writes.

prevents

Application security requirements can specify bounds-checking and safe memory handling.

prevents

Secure architecture and engineering principles reduce the likelihood of buffer overflows.

prevents

Secure coding directly addresses out-of-bounds writes through language choice and coding standards.

prevents

Change management can enforce review gates that catch unsafe memory operations before deployment.

References