CVE-2025-20646
Published: 03 March 2025
Summary
CVE-2025-20646 is a critical-severity Out-of-bounds Write (CWE-787) vulnerability in Mediatek Software Development Kit. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 15.8% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
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
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly requires validation of all inputs to prevent out-of-bounds writes due to improper input validation as in this CVE.
Mandates timely flaw remediation, including applying the vendor patch WCNCR00389074 to eliminate the vulnerability.
Implements memory protections that block exploitation of out-of-bounds writes for remote privilege escalation.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Out-of-bounds write in network-accessible WLAN AP firmware directly enables remote unauthenticated privilege escalation (T1068) via public-facing application exploitation (T1190).
NVD Description
In wlan AP FW, there is a possible out of bounds write due to improper input validation. This could lead to remote escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID:…
more
WCNCR00389074; Issue ID: MSV-1803.
Deeper analysisAI
CVE-2025-20646 is a high-severity vulnerability (CVSS 9.8, CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) involving an out-of-bounds write due to improper input validation (CWE-787) in WLAN Access Point Firmware. Published on March 3, 2025, it affects MediaTek's WLAN AP firmware components, as detailed in the vendor's product security bulletin.
The vulnerability enables remote escalation of privilege without requiring additional execution privileges or user interaction. A network-accessible attacker can exploit it with low complexity over the network, potentially achieving high confidentiality, integrity, and availability impacts by writing outside allocated memory bounds.
MediaTek's March 2025 Product Security Bulletin provides mitigation guidance, including Patch ID WCNCR00389074 for remediation. Security practitioners should review the advisory at https://corp.mediatek.com/product-security-bulletin/March-2025 and apply the specified patch to vulnerable WLAN AP firmware deployments, with Issue ID MSV-1803 for tracking.
Details
- CWE(s)