CVE-2025-5901Public exploitNetwork attack vector

Authenticated code execution via unchecked File copy

Published Jun 9, 2025 · Updated Jun 10, 2025

Stack buffer overflow in TOTOLINK T10 4.1.8cu.5207 allows remote authenticated users to execute code via a crafted POST request. UploadCustomModule in /cgi-bin/cstecgi.cgi passes the attacker-controlled File field to strcpy without checking its length before copying it into a fixed-size stack buffer. Access to the authenticated management interface is required; oversized input can corrupt process memory, crash the CGI service, or execute code on the router.

CVSS severity8.8
High
EPSS probability6.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack buffer overflow in TOTOLINK T10 4.1.8cu.5207 allows remote authenticated users to execute code via a crafted POST request. UploadCustomModule in /cgi-bin/cstecgi.cgi passes the attacker-controlled File field to strcpy without checking its length before copying it into a fixed-size stack buffer. Access to the authenticated management interface is required; oversized input can corrupt process memory, crash the CGI service, or execute code on the router.

The record

CVE
CVE-2025-5901
Published
Jun 9, 2025
Updated
Jun 10, 2025
Vendor
TOTOLINK
Product
T10
Classifications
CWE-120, CWE-119, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 9, 2025CVE publishedPublication date reported by the CVE source.
  2. Jun 10, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.1.8cu.5207

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

TOTOLINK · T10version=4.1.8cu.5207

Published CVSS scores

8.8NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.7VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
9.0VulDBAV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR
8.8VulDBCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
8.8VulDBCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
9.0NVDAV:N/AC:L/Au:S/C:C/I:C/A:C

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.

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No observations available

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

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input
CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
T1190Exploit Public-Facing Application

Public exploit references

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

Technologies

Your stack

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Your stack

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