El mensaje cifrado permite hacer una deducción.

In Spanish, descriptive adjectives usually come after the noun, so mensaje cifrado is the normal order.

• mensaje = message
• cifrado = encrypted / coded

So el mensaje cifrado simply means the encrypted message.

Putting the adjective before the noun is much less common here and would sound literary, unusual, or stylistically marked. For everyday Spanish, mensaje cifrado is the natural choice.

Cifrado means encrypted, coded, or enciphered, depending on context.

It comes from the verb cifrar, which means:

• to encrypt
• to encode
• sometimes to express in figures/numbers, depending on context

In this sentence, mensaje cifrado most naturally means encrypted message or coded message.

Here, cifrado is functioning as an adjective, even though it originally comes from the past participle of cifrar.

This is very common in Spanish. A past participle can describe the state of a noun:

• una puerta cerrada = a closed door
• un documento firmado = a signed document
• un mensaje cifrado = an encrypted message

So in this sentence, cifrado is not the main verb. It is just describing mensaje.

In Spanish, permitir is often followed directly by an infinitive.

So:

• permite hacer = allows one to make / to do
• permite ver = allows one to see
• permite entender = allows one to understand

Spanish does not need a preposition here. English uses to, but Spanish simply uses the infinitive:

• permite hacer una deducción

That structure is completely normal.

Spanish often uses a very common verb like hacer together with a noun, where English might prefer a single verb.

So these are both possible:

• hacer una deducción = to make a deduction
• deducir algo = to deduce something

The version in your sentence sounds natural and slightly formal or analytical. It focuses on the act of making a deduction.

A similar sentence could also be:

• El mensaje cifrado permite deducir algo.

That would also be correct, but it is structured a little differently.

Because deducción is a countable noun here: a deduction.

Spanish often uses an article where English also would:

• hacer una deducción = make a deduction
• tomar una decisión = make a decision
• cometer un error = make an error

Without una, the phrase would sound incomplete in normal Spanish.

All three can fit, depending on context.

Permite comes from permitir, and in this sentence it can mean:

• allows
• makes possible
• enables

So the sentence can be understood as something like:

• The encrypted message allows a deduction.
• The encrypted message makes it possible to make a deduction.
• The encrypted message enables a deduction.

Lets is possible in some contexts, but here allows or makes possible sounds more natural in English.

Because the subject is el mensaje cifrado, which is singular.

Breakdown:

• El mensaje cifrado = singular subject
• permite = he/she/it allows or you allow (formal usted), but here it means it allows

So the verb must be singular:

• El mensaje cifrado permite...

If the subject were plural, the verb would change:

• Los mensajes cifrados permiten... = The encrypted messages allow...

They are often used similarly, but cifrado is generally the more traditional and widely preferred term, especially in careful or technical Spanish.

• mensaje cifrado = very standard
• mensaje encriptado = also common in many places, especially in informal or tech-related speech

A lot of native speakers say both, but learners should know that cifrado is usually the safest and most standard choice.

Yes, that is grammatically possible, but it is a little less natural in many contexts.

Compare:

• permite hacer una deducción = allows one to make a deduction
• permite una deducción = allows/supports a deduction

The version with hacer sounds more like someone can actively arrive at a deduction.
The version without hacer sounds a bit more abstract, as if the message itself permits or supports that conclusion.

So the original sentence is a very natural way to express the idea.

The stress is on the last syllable:

• de-duc-CIÓN

It has a written accent because Spanish spelling rules require it. Words ending in -n, -s, or a vowel are normally stressed on the next-to-last syllable unless an accent mark shows otherwise.

Since deducción is stressed on the last syllable, it needs the accent:

• deducción

This is also a very common noun ending in Spanish:

• acción
• decisión
• conclusión
• deducción

It sounds neutral to slightly formal.

Why?

• mensaje cifrado sounds standard and somewhat technical
• permite hacer una deducción sounds analytical and precise

It would fit well in:

• academic writing
• detective or mystery contexts
• technical explanations
• formal conversation

It is not overly stiff, but it is not especially casual either.