Key Descriptor Version

Which algorithms compute the MIC and wrap the key data.

Reading a capture

Decides how the MIC below is computed, so getting it wrong makes every MIC in the capture fail to validate for a reason that has nothing to do with the passphrase.

Values

Value	Meaning
1	HMAC-MD5 MIC, RC4 key wrap — TKIP era
2	HMAC-SHA1-128 MIC, AES key wrap — WPA2 with CCMP
3	AES-CMAC MIC, AES key wrap

Bit values written b0 first, matching transmission order.

Where it sits

EAPOL-Key > Key Information > Key Descriptor Version

• Open in the explorer — Four-way handshake message 1
• Open in the explorer — Four-way handshake message 2
• Open in the explorer — Four-way handshake message 3
• Open in the explorer — Four-way handshake message 4

Accuracy

Clause

802.11-2024 §12.7.2

Verified

Not verified against the standard. Treat this as a claim, not a fact.