CVE-2026-27651

high F5
CVSS v3 Base Score
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score
0.0%
Exploitation probability in 30 days
Top 88% most likely to be exploited
Attack Characteristics
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Confidentiality
None
Integrity
None
Availability
High
Published: March 24, 2026 (50 days ago)
Last Modified: March 30, 2026
Vendor: F5
Source: NVD

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.

CWE

CWE-476

Affected Products

f5 nginx open sourcef5 nginx plus

References

🔗 my.f5.com