Quick answers
- Is CVE-2026-44041 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-44041 being exploited in the wild.
- How severe is CVE-2026-44041?
- Medium severity, with a CVSS score of 4.3, published 1 July 2026.
- Which products and versions are affected?
- UltraVNC through 1.8.2.2.
- Is there a fix for CVE-2026-44041?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-44041 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-44041?
- Check whether you run UltraVNC at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
An out-of-bounds read vulnerability exists in UltraVNC versions up to 1.8.2.2 within the vncWc2Mb() function in rfb/dh.cpp. The root cause is the function passing a caller-supplied WCHAR pointer to wcslen() before performing any bounds checking. If an attacker provides a wide-character buffer that lacks proper NUL-termination, wcslen() will read past the buffer's end until it encounters a NUL wchar. This can result in an information disclosure of adjacent memory or a process crash (DoS) if the read operation crosses a memory page boundary. While the vendor has released version 1.8.2.4, users should verify if this specific issue is addressed in the latest release.
Affected products
- UltraVNC UltraVNC through 1.8.2.2
Timeline
- 2026-07-01: advisory: Vulnerability published in NVD