CVE-2026-27651

Description

When the ngx_mail_auth_http_module module is enabled on NGINX Plus or NGINX Open Source, undisclosed requests can cause worker processes to terminate. This issue may occur when (1) CRAM-MD5 or APOP authentication is enabled, and (2) the authentication server permits retry by returning the Auth-Wait response header. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

References

https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27651.json

https://my.f5.com/manage/s/article/K000160383

https://bugzilla.redhat.com/show_bug.cgi?id=2450791

https://access.redhat.com/security/cve/CVE-2026-27651

https://access.redhat.com/errata/RHSA-2026:8346

https://access.redhat.com/errata/RHSA-2026:7343

https://access.redhat.com/errata/RHSA-2026:7002

https://access.redhat.com/errata/RHSA-2026:6923

https://access.redhat.com/errata/RHSA-2026:6907

https://access.redhat.com/errata/RHSA-2026:6906

https://access.redhat.com/errata/RHSA-2026:15966

https://access.redhat.com/errata/RHSA-2026:15945

https://access.redhat.com/errata/RHSA-2026:15943

https://access.redhat.com/errata/RHSA-2026:15942

https://access.redhat.com/errata/RHSA-2026:14836

https://access.redhat.com/errata/RHSA-2026:13839

https://access.redhat.com/errata/RHSA-2026:13680

https://access.redhat.com/errata/RHSA-2026:13634

https://access.redhat.com/errata/RHSA-2026:10065

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3

CVSS v4

EPSS