Cyber Resilience

CVE-2025-8817

HighPublic PoC

Published: 10 August 2025

Published
10 August 2025
Modified
04 September 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 0.0089 75.9th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-8817 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Linksys Re6250 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 24.1% 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).

Deeper analysis

CVE-2025-8817 is a stack-based buffer overflow vulnerability affecting the setLan function in the /goform/setLan file on Linksys range extender models RE6250, RE6300, RE6350, RE6500, RE7000, and RE9000 running firmware versions up to 20250801. The issue arises from manipulation of the lan2enabled argument, classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) and CWE-121 (Stack-based Buffer Overflow). It has a CVSS v3.1 base score of 8.8, indicating high severity.

The vulnerability can be exploited remotely over the network with low attack complexity and requires low privileges (PR:L), such as those of an authenticated user, with no user interaction needed. Successful exploitation grants high impacts on confidentiality, integrity, and availability (C:H/I:H/A:H), potentially allowing arbitrary code execution, data compromise, or device disruption via the buffer overflow.

Advisories from VulDB (ctiid.319351, id.319351) and a public GitHub disclosure detail the vulnerability, including a proof-of-concept exploit. The vendor was notified early but has not responded or issued patches, leaving affected devices unmitigated. Security practitioners should isolate or replace vulnerable firmware immediately, as the exploit is publicly available.

EU & UK References

Vulnerability details

A vulnerability was identified in Linksys RE6250, RE6300, RE6350, RE6500, RE7000 and RE9000 up to 20250801. Affected by this vulnerability is the function setLan of the file /goform/setLan. The manipulation of the argument lan2enabled leads to stack-based buffer overflow. The…

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attack can be launched remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

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?

Stack-based buffer overflow in the web management interface (/goform/setLan) of Linksys Wi-Fi range extenders enables remote exploitation of a public-facing application for potential code execution.

CVEs Like This One

CVE-2025-9247Same product: Linksys Re6250
CVE-2025-8819Same product: Linksys Re6250
CVE-2025-9249Same product: Linksys Re6250
CVE-2025-8816Same product: Linksys Re6250
CVE-2025-14134Same product: Linksys Re6250
CVE-2025-9359Same product: Linksys Re6250
CVE-2025-9245Same product: Linksys Re6250
CVE-2025-9483Same product: Linksys Re6250
CVE-2025-9250Same product: Linksys Re6250
CVE-2025-9252Same product: Linksys Re6250

Affected Assets

linksys
re6250 firmware
1.0.04.001
linksys
re6300 firmware
1.2.07.001
linksys
re6350 firmware
1.0.04.001
linksys
re7000 firmware
1.1.05.003
linksys
re9000 firmware
1.0.04.002
linksys
re6500 firmware
1.0.013.001

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly mitigates the stack-based buffer overflow by enforcing validation of inputs like the lan2enabled argument in the setLan function.

prevent

Provides memory protections such as stack canaries, ASLR, and non-executable stacks to prevent exploitation of stack-based buffer overflows.

prevent

Mandates identification, prioritization, and timely patching of firmware flaws like CVE-2025-8817 to eliminate the buffer overflow vulnerability.

References