rxvt-unicode and xterm different yellow colors in journalctl

Recently, I noticed something strange. If I run the command sudo journalctl -f -u ModemManager in rxvt-unicode (left) and xterm (right), in rxvt-unicode the yellow does not appear when the message is a warning. Both terminals have TERM=xterm-256color and I noticed this problem only in yellow, as the red appears in both terminals. I tried different escape sequences, but I was not able to detect the problem. xterm Right: urxvt" class="img-fluid rounded" style="max-width: 100%; height: auto; margin: 10px 0;" loading="lazy">