CVE-2026-44296 (GCVE-0-2026-44296)

Vulnerability from cvelistv5 – Published: 2026-05-12 20:52 – Updated: 2026-05-13 12:18
VLAI
Title
Deskflow: TLS multiplexer DoS on failed `SSL_accept`
Summary
Deskflow is a keyboard and mouse sharing app. Prior to 1.26.0.167, a remote, unauthenticated denial of service (DoS) vulnerability affects Deskflow servers running with TLS enabled (the default). When any TCP peer connects to the listening port and its first bytes do not parse as a valid TLS ClientHello, SecureSocket::secureAccept enters its fatal-error branch and calls Arch::sleep(1) (a blocking 1-second sleep) on the multiplexer worker thread. That thread services every socket on the server, including established TLS clients delivering mouse motion, keyboard events, and clipboard updates. A single failed handshake therefore stalls input delivery to all connected screens for ~1 second, and a sustained drip of malformed connections (≥ 1/s) makes the server effectively unusable while the attack persists. This vulnerability is fixed in 1.26.0.167.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-13 12:14 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-405 - Asymmetric Resource Consumption (Amplification)
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8129 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
deskflow deskflow Affected: < 1.26.0.167
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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