CVE-2026-41476

HighPublic PoC

Published: 24 April 2026

Published

24 April 2026

Modified

28 April 2026

KEV Added

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Patch

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CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Score 0.0006 18.8th percentile

Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-41476 is a high-severity Classic Buffer Overflow (CWE-120) vulnerability in Deskflow Deskflow. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation of Remote Services (T1210); ranked at the 18.8th percentile by exploit likelihood (below the median); 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).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploitation of Remote Services (T1210). What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-10 Information Input Validation good match

prevent

Directly addresses the lack of validation on the internal structure of serialized clipboard blobs, preventing malformed inputs from triggering out-of-bounds reads during deserialization.

SI-16 Memory Protection good match

prevent

Implements memory safeguards like address space randomization and non-executable stacks to mitigate exploitation of memory-safety vulnerabilities such as out-of-bounds reads.

SI-2 Flaw Remediation good match

prevent

Requires timely identification, reporting, and patching of flaws like the clipboard deserialization vulnerability fixed in Deskflow 1.26.0.138.

MITRE ATT&CK Enterprise TechniquesAI

T1210 Exploitation of Remote Services Lateral Movement

Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.

attack.mitre.org →

Why these techniques?

The remote OOB read in Deskflow's clipboard deserialization (via malformed update from a connected peer) directly enables exploitation of the remote service for initial access or impact.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

Deskflow is a keyboard and mouse sharing app. Prior to 1.26.0.138, a remote memory-safety vulnerability in Deskflow's clipboard deserialization allows a connected peer to trigger an out-of-bounds read by sending a malformed clipboard update. The issue is in the implementation…

of src/lib/deskflow/IClipboard.cpp. This is reachable because ClipboardChunk::assemble() in src/lib/deskflow/ClipboardChunk.cpp validates only the outer clipboard transfer size. It does not validate the internal structure of the serialized clipboard blob, so malformed inner lengths reach IClipboard::unmarshall() unchanged. This vulnerability is fixed in 1.26.0.138.

Deeper analysisAI

CVE-2026-41476 is a remote memory-safety vulnerability affecting Deskflow, a keyboard and mouse sharing application, in versions prior to 1.26.0.138. The issue lies in the clipboard deserialization implementation within src/lib/deskflow/IClipboard.cpp. Specifically, ClipboardChunk::assemble() in src/lib/deskflow/ClipboardChunk.cpp validates only the outer clipboard transfer size and fails to check the internal structure of the serialized clipboard blob, allowing malformed inner lengths to propagate unchanged to IClipboard::unmarshall(). This enables a connected peer to trigger an out-of-bounds read (CWE-120) by sending a malformed clipboard update. 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).

A connected peer with low privileges (PR:L) can exploit this vulnerability remotely over the network (AV:N) with low attack complexity (AC:L) and without requiring user interaction (UI:N). Exploitation involves sending a specially crafted clipboard update, which bypasses validation and leads to an out-of-bounds read in the deserialization process. The unchanged scope (S:U) combined with high impacts on confidentiality, integrity, and availability (C:H/I:H/A:H) suggests potential for severe consequences, such as data disclosure, corruption, or denial of service.

The Deskflow GitHub security advisory (GHSA-3jp5-g964-cgmh) confirms the vulnerability is fixed in version 1.26.0.138. Mitigation requires updating to Deskflow 1.26.0.138 or later to address the validation deficiencies in clipboard handling.