Review reviewHigh

CVE-2025-67445

x5000r firmware, x5000r

TOTOLINK X5000R V9.1.0cu.2415_B20250515 contains a denial-of-service vulnerability in /cgi-bin/cstecgi.cgi. The CGI reads the CONTENT_LENGTH environment variable and allocates memory using malloc (CONTENT_LENGTH + 1) without sufficient bounds checking. When lighttpd s request size limit is not enforced, a crafted large POST request can cause memory exhaustion or a segmentation fault, leading to a crash of the management CGI and loss of availability of the web interface.

CVSS: 7.5
EPSS: 0.33%
CISA KEV: Not listed
Published: 2026.02.25

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.33%

Technical severityCVSS 7.5

Vulnerability overview

Affected product and versions

Product: x5000r firmware, x5000r
Affected versions: 9.1.0cu.2415 b20250515
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that x5000r firmware, x5000r and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE: CWE-400