This is the 10224th most frequent Spanish word.
colar
To strain, filter, or sneak.
Here, 'colarse' (a reflexive form) means to sneak or slip into a space without being noticed.
Ella se coló en la fila del cine y nadie se dio cuenta.
She sneaked into the cinema line and no one noticed.
In this context, 'colar' is used figuratively to mean that something undesirable goes unnoticed or gets included where it shouldn't.
Estos datos falsos no deberían colarse en el informe oficial.
These false data should not slip into the official report.
In this sentence, 'colar' is used to refer to the action of filtering or straining something liquid to remove solid pieces.