Cyber Posture

CVE-2025-8243

HighPublic PoC

Published: 27 July 2025

Published
27 July 2025
Modified
29 July 2025
KEV Added
Patch
CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0101 77.3th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-8243 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Totolink X15 Firmware. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 22.7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190). What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Implements input validation mechanisms at HTTP POST endpoints to restrict the devicemac1 argument and prevent buffer overflows.

prevent

Enforces memory protections like non-executable stacks and ASLR to mitigate exploitation of the buffer overflow even if triggered.

prevent

Requires timely identification, reporting, and correction of the specific buffer overflow flaw in the router firmware.

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 public-facing HTTP POST handler (/boafrm/formMapDel) directly enables remote exploitation of the router's web interface for code execution.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

A vulnerability was found in TOTOLINK X15 1.0.0-B20230714.1105 and classified as critical. This issue affects some unknown processing of the file /boafrm/formMapDel of the component HTTP POST Request Handler. The manipulation of the argument devicemac1 leads to buffer overflow. The…

more

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

Deeper analysisAI

CVE-2025-8243 is a critical buffer overflow vulnerability (CVSS v3.1 score of 8.8; AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) affecting the TOTOLINK X15 router on firmware version 1.0.0-B20230714.1105. The flaw exists in an unknown processing function of the HTTP POST Request Handler component, specifically the /boafrm/formMapDel endpoint, where manipulation of the "devicemac1" argument triggers the overflow. It is associated with CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), CWE-120 (Buffer Copy without Bounds Checking), and CWE-787 (Out-of-bounds Write).

A remote attacker with low privileges can exploit this vulnerability by sending a malicious HTTP POST request to the affected endpoint. No user interaction is required, and the low attack complexity enables reliable exploitation. Successful attacks can result in high confidentiality, integrity, and availability impacts, potentially compromising the device.

Advisories on VulDB (e.g., https://vuldb.com/?ctiid.317831, https://vuldb.com/?id.317831) document the issue, with a public exploit disclosed on GitHub (https://github.com/panda666-888/vuls/blob/main/totolink/x15/formMapDel.md). The vendor website (https://www.totolink.net/) is referenced, but no specific patch or mitigation details are provided in the available information.

The exploit has been publicly disclosed and may be used, as noted in the CVE description published on 2025-07-27.

Details

CWE(s)

Affected Products

totolink
x15 firmware
1.0.0-b20230714.1105

CVEs Like This One

CVE-2025-8242Same product: Totolink X15
CVE-2025-8245Same product: Totolink X15
CVE-2025-8246Same product: Totolink X15
CVE-2025-8244Same product: Totolink X15
CVE-2025-9303Same vendor: Totolink
CVE-2026-1155Same vendor: Totolink
CVE-2025-9780Same vendor: Totolink
CVE-2025-9783Same vendor: Totolink
CVE-2026-1328Same vendor: Totolink
CVE-2025-7460Same vendor: Totolink

References