Simple Posts Ticker < 1.1.6 - Contributor+ Stored XSS

Description The plugin does not validate and escape some of its shortcode attributes before outputting them back in a page/post where the shortcode is embed, which could allow users with the contributor role and above to perform Stored Cross-Site Scripting attacks.

PoC

Add a post with the shortcode: [spt-posts-ticker label_text_size='" onmouseover="alert(/XSS/)"' label_text="123123"] View the shortcode and move your mouse over the string 123123 to see the XSS.