When opening a product with the configured Vary by Url option on the SXA storefront, the wrong product details might be shown. The issue happens because the Vary By URL cache option is not taken into account in cache settings for a specific site.
To resolve the issue, download and install the patch or hotfix compatible with the affected product version found on this page:
Be aware that the hotfix was built for a specific Sitecore XC version, and must not be installed on other Sitecore XC versions or in combination with other hotfixes. In case any other hotfixes have already been installed on a certain Sitecore XC instance, send a request for a compatibility check to Sitecore Support.
Note that the ZIP file contents need to be extracted to locate installation instructions and related files inside. The hotfixes must be installed on a CM instance and then synced with other instances using standard development practices.