Critical Cisco IOS XE Flaw Allows Remote File Uploads, Patched

Cisco has addressed a critical vulnerability in its IOS XE Software for Wireless LAN Controllers (WLCs) that could allow unauthenticated, remote attackers to upload arbitrary files to affected systems. The flaw, identified as CVE-2025-20188, carries a maximum CVSS score of 10, underscoring its severity. The vulnerability resides in the Out-of-Band Access Point (AP) Image Download, the Clean Air Spectral Recording, and the client debug bundles features of the software. Exploitation of this flaw could potentially enable attackers to gain root access via the manipulation of JSON Web Tokens (JWTs), as noted in recent security analyses. Given its critical nature, the vulnerability poses a significant risk to organizations using Cisco's wireless LAN controllers. Attackers leveraging this flaw could compromise network security by uploading malicious files, potentially leading to further exploitation or data breaches. Cisco has released patches to mitigate this vulnerability, and organizations are strongly advised to apply these updates immediately to protect their systems. The vulnerability's Exploit Prediction Scoring System (EPSS) score is relatively low at 0.039, indicating a lower likelihood of exploitation in the wild, but the critical nature of the flaw warrants prompt action. Security teams should prioritize patching affected systems and review their network configurations to ensure no unauthorized access points are present. Monitoring for unusual activity related to file uploads or JWT manipulations can also help in early detection of potential exploitation attempts.