MEDIUM · 4.3

CVE-2025-23419

When multiple server blocks are configured to share the same IP address and port, an attacker can use session resumption to bypass client certificate authentication requirements on these servers. This...

Vulnerability Description

When multiple server blocks are configured to share the same IP address and port, an attacker can use session resumption to bypass client certificate authentication requirements on these servers. This vulnerability arises when TLS Session Tickets https://nginx.org/en/docs/http/ngx_http_ssl_module.html#ssl_session_ticket_key are used and/or the SSL session cache https://nginx.org/en/docs/http/ngx_http_ssl_module.html#ssl_session_cache are used in the default server and the default server is performing client certificate authentication.   Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

CVSS Score

4.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE

Affected Products

VendorProductVersions
F5Nginx>= 1.11.4, < 1.26.3
F5Nginx Plus>= r28, < r32
DebianDebian Linux11.0

Related Weaknesses (CWE)

References

FAQ

What is CVE-2025-23419?

CVE-2025-23419 is a vulnerability with a CVSS score of 4.3 (MEDIUM). When multiple server blocks are configured to share the same IP address and port, an attacker can use session resumption to bypass client certificate authentication requirements on these servers. This...

How severe is CVE-2025-23419?

CVE-2025-23419 has been rated MEDIUM with a CVSS base score of 4.3/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2025-23419?

Check the references section above for vendor advisories and patch information. Affected products include: F5 Nginx, F5 Nginx Plus, Debian Debian Linux.