diff --git a/src/quic/tls13.zig b/src/quic/tls13.zig
index 33229fe..e788353 100644
--- a/src/quic/tls13.zig
+++ b/src/quic/tls13.zig
@@ -1827,19 +1827,21 @@ pub const Tls13Handshake = struct {
 
         // Decrypt ticket identity to get PSK
         if (identity_len < 16 + 1) return; // at least tag + 1 byte
+        var decrypted: [64]u8 = undefined;
+        var ct_copy: [decrypted.len + 16]u8 = undefined;
+        if (identity_len > ct_copy.len) return;
         const ciphertext_len = identity_len - 16;
+        if (ciphertext_len > decrypted.len) return;
 
         // Reconstruct nonce from ticket (we use the last 4 bytes of identity as hint)
         var ticket_nonce: [12]u8 = .{0} ** 12;
         // Use zeros as nonce — server encrypts with incrementing nonce_buf in [8..12]
         // We need to try nonce counter values. For simplicity, try a few.
-        var decrypted: [64]u8 = undefined;
         var psk_found = false;
         var found_psk: [32]u8 = undefined;
 
         for (0..256) |nonce_try| {
             std.mem.writeInt(u32, ticket_nonce[8..12], @intCast(nonce_try), .big);
-            var ct_copy: [80]u8 = undefined;
             @memcpy(ct_copy[0..identity_len], identity[0..identity_len]);
             const tag_start = ciphertext_len;
             const tag: [16]u8 = ct_copy[tag_start..][0..16].*;
@@ -3104,6 +3106,33 @@ test "loopback PSK resumption: two handshakes with session ticket" {
     );
 }
 
+test "tryProcessPsk rejects oversized ticket identity before decrypt" {
+    const tp = transport_params.TransportParams{
+        .initial_max_data = 1048576,
+        .initial_max_streams_bidi = 100,
+    };
+
+    const server_config = TlsConfig{
+        .cert_chain_der = &.{},
+        .private_key_bytes = &.{},
+        .alpn = &[_][]const u8{"h3"},
+        .ticket_key = .{0xA5} ** 16,
+    };
+
+    var handshake = Tls13Handshake.initServer(server_config, tp);
+
+    var psk_ext: [124]u8 = .{0} ** 124;
+    std.mem.writeInt(u16, psk_ext[0..2], 87, .big);
+    std.mem.writeInt(u16, psk_ext[2..4], 81, .big);
+    std.mem.writeInt(u32, psk_ext[85..89], 0, .big);
+    std.mem.writeInt(u16, psk_ext[89..91], 33, .big);
+    psk_ext[91] = 32;
+
+    handshake.tryProcessPsk("", "", 0, &psk_ext, 0, psk_ext.len);
+
+    try std.testing.expect(!handshake.using_psk);
+}
+
 // NewSessionTicket roundtrip test
 test "NewSessionTicket: build and parse roundtrip" {
     const psk: [32]u8 = .{0x55} ** 32;