CVE-2025-7921: ASKEY｜modem - Stack-based Buffer Overflow

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-07-21 · updated 2026-06-17
Weakness: CWE-121

Description

Certain modem models developed by Askey has a Stack-based Buffer Overflow vulnerability, allowing unauthenticated remote attackers to control the program's execution flow and potentially execute arbitrary code.

Affected products

ASKEY RTF8207w: before R82XXR250718 — fixed in R82XXR250718
ASKEY RTF8217: before R82XXR250718 — fixed in R82XXR250718

How to fix

Upgrade to a fixed version: ASKEY RTF8207w R82XXR250718; ASKEY RTF8217 R82XXR250718. Check the vendor advisory for mitigations.

References

https://www.twcert.org.tw/en/cp-139-10269-c9839-2.html
https://www.twcert.org.tw/tw/cp-132-10268-1583b-1.html

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