Cyber Resilience

CVE-2025-5902

HighPublic PoC

Published: 09 June 2025

Published
09 June 2025
Modified
16 June 2025
KEV Added
Patch
CVSS Score v4 7.4 CVSS: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/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 0.0142 81.0th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-5902 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Totolink T10 Firmware. Its CVSS base score is 7.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 19.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis

A vulnerability classified as critical was identified in the TOTOLINK T10 firmware version 4.1.8cu.5207. It resides in the setUpgradeFW function within the /cgi-bin/cstecgi.cgi component that handles POST requests. The flaw is triggered by improper handling of the slaveIpList argument, resulting in a buffer overflow condition associated with CWE-119 and CWE-120.

An attacker with network access and valid low-privileged credentials can send a crafted POST request to trigger the overflow remotely. Successful exploitation grants the ability to compromise confidentiality, integrity, and availability on the affected device, with the public disclosure of exploit details increasing the likelihood of active use.

The listed references include a detailed disclosure on a Notion page, entries on VulDB, and the vendor site, but provide no explicit information on patches or mitigation steps. The EPSS score remains low and essentially unchanged at approximately 0.014, indicating limited observed exploitation interest to date.

EU & UK References

Vulnerability details

A vulnerability was found in TOTOLINK T10 4.1.8cu.5207 and classified as critical. This issue affects the function setUpgradeFW of the file /cgi-bin/cstecgi.cgi of the component POST Request Handler. The manipulation of the argument slaveIpList leads to buffer overflow. The attack…

more

may be initiated remotely. The exploit has been disclosed to the public and may be used.

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?

Buffer overflow in the public-facing web CGI endpoint (/cgi-bin/cstecgi.cgi setUpgradeFW) via POST request with manipulated slaveIpList enables remote exploitation of a public-facing application.

Affected Assets

totolink
t10 firmware
4.1.8cu.5207

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-119 CWE-120

Managed runtimes used by platform-independent applications (e.g., JVM, CLR) enforce memory safety, preventing most buffer overflows that require direct memory manipulation.

addresses: CWE-119

Ongoing control assessments and code testing (static/dynamic analysis, fuzzing) surface memory buffer restriction failures, which are then remediated before release.

addresses: CWE-119

Memory protections (e.g., W^X, ASLR) make exploitation of buffer-boundary violations far harder to turn into code execution.

addresses: CWE-119

Detects exploitation attempts that produce memory corruption, crashes, or anomalous behavior.

References