Cyber Resilience

CVE-2018-25299

Memory Safety

Public PoCMemory Safety
Published
29 April 2026
Modified
30 April 2026
CVSS Score v4 8.6
Click a component to see what it means
Raw vectorCVSS:4.0/AV:L/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 0.0016 6th percentile
Risk Priority 35 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2018-25299 is a high-severity Classic Buffer Overflow (CWE-120) vulnerability in Mersenne (inferred from references). Its CVSS base score is 8.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 6th percentile by exploit likelihood (below the median); 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 SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — 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-2018-25299 is a local buffer overflow vulnerability (CWE-120) in Prime95 version 29.4b8, a software tool used for Mersenne prime hunting and stress-testing. The flaw resides in the PrimeNet connection settings, where the optional proxy hostname field can be abused to inject a malicious payload, triggering a structured exception handling (SEH) overwrite that enables arbitrary code execution. It carries a CVSS v3.1 base score of 8.4 (AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating high severity due to its potential for complete system compromise.

A local attacker can exploit this vulnerability with low attack complexity and no user privileges or interaction required. By supplying a specially crafted string in the proxy hostname field, the attacker triggers the buffer overflow, hijacks SEH control flow, and executes arbitrary system commands, potentially leading to full control over the affected system including data theft, modification, or denial of service.

Advisories and references, including Vulncheck's detailed analysis of the Prime95 29.4b8 SEH overflow and an Exploit-DB proof-of-concept (ID 44649), confirm the issue without specifying patches. The official Prime95 site at mersenne.org and its download page provide access to the software, where users should check for updated versions beyond 29.4b8 to mitigate exposure.

EU & UK References

Vulnerability Data

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…

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the overflow and execute system commands.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
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.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-20189Shared CWE-120
CVE-2024-20450Shared CWE-120
CVE-2025-50648Shared CWE-120
CVE-2024-39769Shared CWE-120
CVE-2026-64767Shared CWE-120
CVE-2024-39288Shared CWE-120
CVE-2023-35980Shared CWE-120
CVE-2024-46584Shared CWE-120
CVE-2024-23973Shared CWE-120
CVE-2025-37891Shared CWE-120

Affected Assets

Mersenne
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V5.2.1

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and analysis can find missing size checks before deployment.

Input validation directly enforces size checks before buffer copies.

Engineering principles require bounds checking and safe buffer handling in design.

Memory protection limits the impact of an overflow once it occurs.

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.

ID.RA-01 partial match
prevents

Vulnerability identification processes such as code review or scanning detect classic buffer overflows before exploitation.

PR.PS-02 partial match
prevents

Routine patching replaces vulnerable code containing unchecked buffer copies with corrected versions.

PR.PS-06 partial match
prevents

Secure development practices directly enforce bounds checking and input validation that prevent classic buffer overflows.

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.

prevents

Secure development life cycle mandates processes that can include input validation and bounds checking to prevent buffer overflows.

prevents

Application security requirements can specify input-size validation and safe buffer handling to mitigate classic buffer overflows.

prevents

Secure system architecture and engineering principles promote defensive coding patterns that reduce the likelihood of unchecked buffer copies.

prevents

Secure coding directly requires bounds-checked memory operations, addressing the root cause of CWE-120.

finds

Security testing in development and acceptance can detect buffer overflows through fuzzing and static analysis, though it does not prevent them at the source.

References