CVE-2025-8820
Published: 11 August 2025
Summary
CVE-2025-8820 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-2025-8820 is a stack-based buffer overflow vulnerability (CWE-119, CWE-121) affecting the wirelessBasic function in the /goform/wirelessBasic file on Linksys Wi-Fi range extenders, specifically models RE6250, RE6300, RE6350, RE6500, RE7000, and RE9000 with firmware versions up to 20250801. The flaw is triggered by manipulating the submit_SSID1 argument, which leads to improper bounds checking and overflow conditions.
The vulnerability carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), enabling remote exploitation over the network with low attack complexity by an attacker possessing low privileges, such as an authenticated user, and without requiring user interaction. Successful exploitation could grant high-impact consequences, including unauthorized access to sensitive data, modification of system integrity, and denial of service through potential remote code execution.
Advisories from VulDB and a public GitHub disclosure detail a proof-of-concept exploit, noting that the vendor was contacted early but provided no response or patches as of the CVE publication on 2025-08-11. No official mitigations are available, and the exploit has been made public, increasing the risk of active use; practitioners should isolate affected devices, restrict administrative access, and monitor for any future firmware updates.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-24102
Vulnerability details
A vulnerability was determined in Linksys RE6250, RE6300, RE6350, RE6500, RE7000 and RE9000 up to 20250801. This vulnerability affects the function wirelessBasic of the file /goform/wirelessBasic. The manipulation of the argument submit_SSID1 leads to stack-based buffer overflow. The attack can…
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be initiated 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
Why these techniques?
Stack buffer overflow in wirelessBasic web form (submit_SSID1) enables remote code execution against the device's HTTP interface.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly mitigates the stack-based buffer overflow by enforcing validation and bounds checking on inputs like the submit_SSID1 argument in the wirelessBasic function.
Provides runtime memory protections such as stack canaries, DEP, and ASLR to prevent exploitation of the stack-based buffer overflow for remote code execution.
Requires identification, reporting, and timely remediation of flaws like this buffer overflow vulnerability through firmware updates or removal of affected devices.