This article provides a detailed analysis of CVE-2025-66270, a medium severity vulnerability affecting KDE Connect and related applications. Understanding this vulnerability is crucial for users and administrators to ensure the security of their systems.
Overview
CVE-2025-66270 describes a flaw in the KDE Connect protocol 8 where device IDs are not properly correlated across different packets. This can potentially lead to security issues due to the inability to reliably identify and verify the source of communication. This vulnerability affects various implementations of KDE Connect, including the desktop version, iOS and Android apps, as well as GSConnect and Valent.
Technical Details
The core of the vulnerability lies in the lack of consistent device ID tracking across packets. The protocol implementation does not ensure that subsequent packets originate from the same verified device as the initial connection. This absence of correlation can be exploited to potentially impersonate devices or inject malicious data into the communication stream. The vulnerability affects KDE Connect protocol 8 before the fixes implemented on November 28, 2025.
Affected Versions:
- KDE Connect before 25.12 on desktop
- KDE Connect before 0.5.4 on iOS
- KDE Connect before 1.34.4 on Android
- GSConnect before 68
- Valent before 1.0.0.alpha.49
CVSS Analysis
- CVSS Score: 4.7 (Medium)
- This score reflects the moderate impact of the vulnerability. While not critical, it requires attention to prevent potential exploitation.
Possible Impact
Although the CVSS score is Medium, successful exploitation of CVE-2025-66270 could lead to:
- Device Impersonation: An attacker could potentially impersonate a trusted device, gaining unauthorized access to resources or functionalities.
- Data Injection: Malicious data could be injected into the communication stream, potentially compromising the integrity of the system.
- Man-in-the-Middle Attacks: While not directly enabling MITM, this vulnerability could facilitate such attacks by making it easier to spoof device identities.
Mitigation or Patch Steps
To mitigate the risks associated with CVE-2025-66270, it is highly recommended to update to the latest versions of the affected software:
- KDE Connect (Desktop): Update to version 25.12 or later.
- KDE Connect (iOS): Update to version 0.5.4 or later.
- KDE Connect (Android): Update to version 1.34.4 or later.
- GSConnect: Update to version 68 or later.
- Valent: Update to version 1.0.0.alpha.49 or later.
Updating ensures that the fix for this vulnerability, implemented after 2025-11-28, is applied to your system.
References
- GSConnect Commit: a38246deec0af50ae218cdc51db32cdd7eb145e3
- Valent Commit: 85f773124a67ed1add79e7465bb088ec667cccce
- KDE Connect (Android) Commit: 675d2d24a1eb95d15d9e5bde2b7e2271d5ada6a9
- KDE Connect (iOS) Commit: 6c003c22d04270cabc4b262d399c753d55cf9080
- KDE Connect (Desktop) Commit: 4e53bcdd5d4c28bd9fefd114b807ce35d7b3373e
- KDE Security Advisory: 20251128-1
