# CVE-2026-63409: deskflow: Deskflow is a keyboard and mouse sharing app

CVE-2026-63409 is fixed in deskflow on 1 platform by DEBIAN-CVE-2026-63409 (version 1.26.0+dfsg-4), released August 31, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-63409
- Priority: High
- CVSS: 8.2 (high)
- EPSS: 0.0045
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 17, 2026

## Description

Deskflow is a keyboard and mouse sharing app. From 1.17.0 until continuous build 1.26.0.296, a malicious Deskflow server can send an odd-length DSOP vector to ServerProxy::setOptions() in src/lib/client/ServerProxy.cpp, causing the missing value after the final option key to be read beyond the vector during the PacketStreamFilter::filterEvent to ServerProxy::handleData() to ServerProxy::parseHandshakeMessage() call chain and crash the connected client. This issue is fixed in continuous build 1.26.0.296.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | deskflow Debian 14 | 1.26.0+dfsg-4 | [DEBIAN-CVE-2026-63409](https://patchblox.com/security/data/fix/linux/debian-cve-2026-63409.md) | Aug 31, 2026 |

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Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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