@@ -469,7 +469,8 @@ impl Verifier for BruteforceVerifier {
                 OP_DUP
                 { -1 }
                 OP_NUMNOTEQUAL OP_VERIFY
-                OP_FROMALTSTACK OP_DROP
+                OP_FROMALTSTACK 
+                { -1 } OP_EQUALVERIFY // Verify the sentinel value -1 to avoid altstack overflow in the rare case where pk == hash160^n(pk).
                 OP_TOALTSTACK
             }
         }
Original file line number	Diff line number	Diff line change
`@@ -469,7 +469,8 @@ impl Verifier for BruteforceVerifier {`
`469`	`469`	`OP_DUP`
`470`	`470`	`{ -1 }`
`471`	`471`	`OP_NUMNOTEQUAL OP_VERIFY`
`472`		`- OP_FROMALTSTACK OP_DROP`
	`472`	`+ OP_FROMALTSTACK`
	`473`	`+ { -1 } OP_EQUALVERIFY // Verify the sentinel value -1 to avoid altstack overflow in the rare case where pk == hash160^n(pk).`
`473`	`474`	`OP_TOALTSTACK`
`474`	`475`	`}`
`475`	`476`	`}`