Deskflow 1.26.0.134/1.26.0.138/1.26.0.167 ServerProxy ServerProxy.cpp parseHandshakeMessage out-of-bounds

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.6$0-$5k0.00+

Summaryinfo

A vulnerability labeled as critical has been found in Deskflow. This issue affects the function ServerProxy::parseHandshakeMessage of the file src/lib/client/ServerProxy.cpp of the component ServerProxy. Executing a manipulation can lead to out-of-bounds. This vulnerability is registered as CVE-2026-63409. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability has been found in Deskflow and classified as critical. This vulnerability affects the function ServerProxy::parseHandshakeMessage of the file src/lib/client/ServerProxy.cpp of the component ServerProxy. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability was named CVE-2026-63409 since 07/16/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details are known, but there is no available exploit.

Upgrading to version 1.26.0.296 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.7
VulDB Meta Temp Score: 7.6

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.2
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Deskflow 1.26.0.296

Timelineinfo

07/16/2026 CVE reserved
08/17/2026 +32 days Advisory disclosed
08/17/2026 +0 days VulDB entry created
08/17/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-63409 (🔒)
GCVE (CVE): GCVE-0-2026-63409
GCVE (VulDB): GCVE-100-391450

Entryinfo

Created: 08/17/2026 23:19
Changes: 08/17/2026 23:19 (65)
Complete: 🔍
Cache ID: 216::103

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