CVE-2026-123611 — LOW (3.7)

Vulnerability Description

rustls before 0.23.46 contains a key exchange downgrade vulnerability that allows network attackers to poison the per-server-name key-exchange group record via an unauthenticated ServerHello. Attackers can answer one connection with a ServerHello selecting X25519, causing later ClientHellos to send only classical shares and lose post-quantum confidentiality.

CVSS Score

3.7

LOW

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

Attack Vector

NETWORK

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

LOW

Integrity

NONE

Availability

NONE

Related Weaknesses (CWE)

CWE-757

References

FAQ

What is CVE-2026-123611?

CVE-2026-123611 is a vulnerability with a CVSS score of 3.7 (LOW). rustls before 0.23.46 contains a key exchange downgrade vulnerability that allows network attackers to poison the per-server-name key-exchange group record via an unauthenticated ServerHello. Attacker...

How severe is CVE-2026-123611?

CVE-2026-123611 has been rated LOW with a CVSS base score of 3.7/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-123611?

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