Nginx: SSL session reuse vulnerability (CVE-2025-23419)

Nginx: SSL session reuse vulnerability (CVE-2025-23419)

Severity

4

CVSS

(AV:L/AC:M/Au:N/C:P/I:P/A:P)

Published

02/06/2025

Created

02/07/2025

Added

02/06/2025

Modified

02/10/2025

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 whenTLS Session Tickets https://nginx.org/en/docs/http/ngx_http_ssl_module.html#ssl_session_ticket_keyare used and/or theSSL session cache https://nginx.org/en/docs/http/ngx_http_ssl_module.html#ssl_session_cacheare 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.

Solution(s)

• nginx-nginx-upgrade-1_26_3
• nginx-nginx-upgrade-1_27_4

References

• https://attackerkb.com/topics/cve-2025-23419
• CVE - 2025-23419