CVE-2026-123612 — LOW (2.3)

Vulnerability Description

rustls 0.23.44 and 0.23.45 contain an information disclosure vulnerability that sends application data buffered before the handshake completes to the client-facing server when Encrypted Client Hello is rejected. Because start_traffic() queues plaintext from ClientConnection::writer() before sending the ech_required alert, the authenticated public_name server receives data intended for the inner server.

CVSS Score

2.3

LOW

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

HIGH

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

LOW

Integrity

NONE

Availability

NONE

Related Weaknesses (CWE)

CWE-696

References

FAQ

What is CVE-2026-123612?

CVE-2026-123612 is a vulnerability with a CVSS score of 2.3 (LOW). rustls 0.23.44 and 0.23.45 contain an information disclosure vulnerability that sends application data buffered before the handshake completes to the client-facing server when Encrypted Client Hello i...

How severe is CVE-2026-123612?

CVE-2026-123612 has been rated LOW with a CVSS base score of 2.3/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-123612?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.