paicoding from commit b8206b9 through commit 903adce uses predictable credentials for accounts created via ZSXQ login, because loginByZsxq derives both the username and password solely from the member's ZSXQ number. Unauthenticated attackers can read that number from the victim's /user/{userId} profile page, compute the credentials, and log in via /login/username to take over the account.

paicoding 1.0.3 contains a missing authorization vulnerability in the ArticleRestController article detail endpoint that allows unauthenticated attackers to read restricted articles. Attackers can enumerate article IDs via GET /article/api/data/detail/{articleId} to retrieve full content of paid, login-only, member-only and draft articles.

paicoding 1.0.3 contains a payment bypass vulnerability that allows authenticated attackers to unlock paid articles by guessing weak payment confirmation codes. Attackers can start a payment, enumerate roughly 2000 IdUtil.genPayCode counter values, and submit the matching verifyCode to the unauthenticated callback to mark it paid.

paicoding commit 766c48b through commit 903adce contains a stored cross-site scripting vulnerability in payment notifications, where NotifyMsgListener inserts the payer's display name unescaped and notify-system-item.html renders it via th:utext. Authenticated attackers can set a malicious display name and start a pending payment on a paid article, executing script in the author's browser when the author views notifications.