CVE-2026-44042

Name of the Vulnerable Software and Affected Versions UltraVNC repeater versions prior to 1.8.2.3

Description An off-by-one error exists in the Base64 decode helper used for HTTP Basic authentication. The wi uudecode() function in the file repeater/webgui/webutils.c uses a strict greater-than comparison when checking if the input length exceeds the output buffer, instead of a greater-than-or-equal comparison. This creates a latent condition that could allow a one-byte write at the boundary of a 1024-byte stack buffer if buffering constraints change.

Recommendations Update UltraVNC repeater to a version newer than 1.8.2.2.