From 6e68889b35302408218b3d60a99abde5ffcfaa87 Mon Sep 17 00:00:00 2001
From: fen <fen@archfox.org>
Date: Fri, 16 Oct 2026 16:59:41 -0500
Subject: [PATCH] Reject negative multipart burn_after_reads via
 parseBurnAfterReads

---
 internal/api/attachments.go | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/internal/api/attachments.go b/internal/api/attachments.go
index 6bdb31b..5a2cfff 100644
--- a/internal/api/attachments.go
+++ b/internal/api/attachments.go
@@ -197,6 +197,12 @@ func (a *apiServer) handleCreatePasteMultipart(w http.ResponseWriter, r *http.Re
 				writeErrCode(w, 400, "burn_invalid", "burn_after_reads must be a positive number")
 				return
 			}
+			// negative values are invalid too: same 400 burn_invalid shape
+			// as the JSON path (validate.go:92), identical message text.
+			if err := parseBurnAfterReads(n); err != nil {
+				writeErrCode(w, 400, "burn_invalid", err.Error())
+				return
+			}
 			p.BurnAfterReads = &n
 		}
 	}