What happens if no CertificateVerify is sent in TLS?

I know in TLS, the client would send a CertificateVerify message for the server to confirm the client’s identity through means such as CA but what if the client never sent this information?

Is it possible for an attacker to use this opportunity to hijack the client’s session through packet sniffing and create it’s own "pre-master secret" to communicate with the server?

What happens if you put a bag of holding in a bag of holding while being in the astral plane?

I know that putting a bag of holding in a bag of holding destroys both and creates a portal to the astral plane, but what would happen if a player chooses to put a bag of holding in a back of holding while being in the astral plane?

Would nothing happen? Would you be transported to a realm of chaos? Any answers would be appreciated!

What happens when allies occupy the same space?

According to “Moving Around Other Creatures” (PH p. 191 / SRD p. 92):

You can move through a nonhostile creature’s space. […] another creature’s space is difficult terrain for you. Whether a creature is a friend or an enemy, you can’t willingly end your move in its space.

So it’s possible for Alice to move into an ally’s space, attack from there, then move out, the only penalty being that the ally’s space counts as difficult terrain to enter.

If an enemy adjacent to the ally’s space has readied a grapple against Alice and is successful, then Alice (unwillingly) ends her move in her ally’s space.

Do allied characters in the same space suffer any negative effect?

Now the rest of Alice’s allies do the same thing.

Is there a limit to the number of characters that can be stacked on a space?

What if Alice’s ally was the one with the readied grapple?

Can you stack an ally on your space by readying a grapple to prevent them from leaving?

What happens when I redirect an attack with mounted combatant but I am outside the reach of their weapon on a grid?

The mounted combatant feat (PHB 168) allows someone to "force an attack targeted at your mount to target you instead."

Suppose I am playing on a grid. Let E be enemies without reach/ranged weapons. M be the spaces a large mount occupies. And R be the space I occupy while riding the mount.

$ \begin{array}{|l|l|r|} \hline \text{E} & \ \hline \text{E} & \text{M} & \text{R}\ \hline \text{E} & \text{M} & \text{M} \ \hline \end{array} $

What happens when I redirect an attack with mounted combatant but I am outside the reach of their weapon on a grid?

What happens to a thrown weapon after it hits or miss?

Patty the Chatty Monk throws her handaxe to a growling wolf. It hits!
So… what happens?
This question is asked for the intent of further understanding the Object Interaction rule and also to add flavor to combat encounters. What happens to a thrown weapon after it is used?

On a hit: does it fall to the ground near the target’s feet? Does it impale/latch/stick to the target? What about armored targets?

On a miss: does it land on the ground near the target’s feet? Or does it travel the maximum distance (assuming there’s nothing blocking its path) in a straight direction before landing? Can it accidentally hit a different target?

In any case, can anyone pick it up and use it again?

What happens if a sender changes the TCP window size over multiple packets that have the same ACK number?

I’m currently doing research on evasion attacks that seek to bypass a Deep-learning based Network Intrusion Detection System.

In order to achieve this, I need to know what the constraints are for the TCP window size field in the TCP packet header. Imagine a client has just sent the last TCP-ACK packet to a server in order to complete the 3-way handshake. He then immediately proceeds to send a GET request to the server (these 2 packets are thus sent one after the other, and contain the same ACK-number).

What happens if the TCP window size in the TCP-ACK packet does not match the window size in the TCP packet containing the GET request? Will the receiver simply observe the last value for the window size that he obtained? Or will there be a violation in the TCP protocol in any way? You can assume that the change in window size is very small, and will not cause the buffer to be full.

More generally, if the client sends N uninterrupted packets (e.g. a heavy-load POST request), can he change the window size in each packet header without repercussions?

What happens when someone fills in a contact form on a website?

I am trying to debug a problem on a website I am working on. The contact form doesn’t work. In my quest to find answers it occurred to me that I don’t even actually know what’s going on in the background in order to understand the sites that I’m reading for help!

So basically my question is: what happens when someone submits a form on a website?

I see that my hosting company has provided me a mail box with some arbitrary email address where the form submission gets returned to when it fails. Why? Do all form submissions actually come from this email address? What does PHP or SMTP have to do with this?

What happens when a caster targets an object that looks like a creature with a spell that targets only creatures?

There are many spells which explicitly target creatures:

Choose one creature within range

The target creature is normally supposed to make a saving throw in this case.

What happens when the caster chooses a creature, that is actually an object? For instance, a scarecrow, a mannequin, an illusion, or a corpse.


  • An evil mage is hiding in the bushes. He casts an illusion of himself on the road, using the Silent Image spell. A PC sorcerer walks down the road, sees the illusion and casts Magic Missile on it.

  • A cleric is standing near a pile of dead bodies. He has suspicions that a few corpses are actually undead creatures. He casts Sacred Flame on every corpse, see which if them succeed, hence, reveals the undead.

  • A wizard casts Acid Splash on a mannequin, trying to damage it with acid.

Possible outcomes I can think of are:

  1. The caster cannot even try to cast the spell, regardless of their information about what the target actually is.
  2. The caster tries to cast the spell, the casting fails, not expending the spell slot.
  3. The caster casts the spell, it expends the spell slot, then fails.
  4. The caster casts the spell, but it hits the original and not the illusion.
  5. The caster casts the spell, it flies to the target illusion but deals no damage to it (passes through it).

References in the rules and Sage advice

I was trying to investigate, but it didn’t make things clearer:

  • Does magic missile hit silent image's illusory creature? has an answer, that Magic Missile won’t hit. It says nothing about if it can be targeted at all, it leaves it up to the DM.

  • Magic Missile automatically finds the original, even when the caster targets an illusion. At least when the illusion was created by the Mirror Image spell. Now confirmed by Jeremy Crawford. This supports the counter-intuitive option 4.

on the other hand

  • Casters don’t automatically know when a spell fails, if there were no perceivable effects (let’s say you can try to cast the Command spell on an illusion). That assumes that casters can waste their spells on illusion, which means they at least can target it. This supports options 3 and 5.