Valve · Report #541020
GetGlobalAchievementPercentagesForApp is missing the same release checks as GetSchemaForGame
How it was found
GetGlobalAchievementPercentagesForApp API method can be used to reveal achievement names/percentages for games that have not been released yet.
This is not a problem with GetSchemaForGame method, which leads me to believe the other method is missing all the relevant checks.
https://api.steampowered.com/ISteamUserStats/GetGlobalAchievementPercentagesForApp/v2/?gameid=██████ https://api.steampowered.com/ISteamUserStats/GetSchemaForGame/v1/?appid=████
GetGlobalAchievementPercentagesForApp should have the same release state checks as GetSchemaForGame as to not leak achievement names.
Impact
This can be used to reveal and leak work-in-progress achievements for games that have not been released yet.