CVE-2026-93304

A (D)TLS 1.2 client can accept a ChangeCipherSpec message before it has sent its ClientKeyExchange. No master secret has been derived at that point, so the client installs read keys derived from a known (deterministic) key and checks the server's Finished against that same key. An out-of-order ChangeCipherSpec can therefore be used by an attacker to complete the handshake in place of the server and send data the client accepts as authentic. The client's own traffic still uses correctly derived keys, so the attacker cannot read it, and the genuine server never completes the handshake. DTLS 1.2 clients are exposed because a datagram read can deliver the out-of-order records on its own. TLS 1.2 clients are exposed when the application supplies received bytes with wolfSSL_inject() or enables read ahead. For certificate suites, the attacker must be in a man-in-the-middle position. For PSK (Pre Shared Key) connections, any fake server can succeed without knowing the PSK.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfSSL/wolfssl/pull/11458	Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

History

02 Oct 2026, 18:41

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 3.7
First Time		Wolfssl wolfssl Wolfssl
References	~~() https://github.com/wolfSSL/wolfssl/pull/11458 -~~	() https://github.com/wolfSSL/wolfssl/pull/11458 - Patch
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::

27 Sep 2026, 10:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-27 10:16

Updated : 2026-10-02 18:41

NVD link : CVE-2026-93304

Mitre link : CVE-2026-93304

CVE.ORG link : CVE-2026-93304

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-696

Incorrect Behavior Order

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