CVE-2025-25567Public exploit

Local vpncmd crash via unchecked numeric input

Published Mar 12, 2025 · Updated Jul 19, 2025

Stack buffer overflow in SoftEther VPN 5.02.5187 allows local users to crash vpncmd by entering an oversized numeric field. UniToInt passes a 128-byte stack buffer to UniToStrForSingleChars, which ignores its dst_size argument and copies every input character into that buffer. The supplier states that only an administrator deliberately entering a long value in the local vpncmd UI can trigger the crash, and it disputes any security impact beyond that user's own process.

CVSS severity9.8
Critical
EPSS probability0.59%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stack buffer overflow in SoftEther VPN 5.02.5187 allows local users to crash vpncmd by entering an oversized numeric field. UniToInt passes a 128-byte stack buffer to UniToStrForSingleChars, which ignores its dst_size argument and copies every input character into that buffer. The supplier states that only an administrator deliberately entering a long value in the local vpncmd UI can trigger the crash, and it disputes any security impact beyond that user's own process.

The record

CVE
CVE-2025-25567
Published
Mar 12, 2025
Updated
Jul 19, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-120
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Mar 12, 2025CVE publishedPublication date reported by the CVE source.
  2. Jul 19, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8CISA ADP VulnrichmentCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo