CVE-2026-27651
NGINX ngx_mail_auth_http_module vulnerability
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.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:NIntegrityNone
A:HAvailabilityHigh
Weaknesses
Affected Products
NGINX Inc.
commercial·USaka nginx, njs, nginx plus
F5
commercial·US
ООО «Ред Софт»
commercial·RUaka red soft
АО «ИВК»
commercial·RUaka ivk
ООО "Веб-Сервер"
commercial·RUaka angie adc, angie, angie pro
and 3 more affected products View all →
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.
MITRE ATT&CK
2 techniques Impact
Initial Access
References
https://my.f5.com/manage/s/article/K000160383
my.f5.com
https://angie.software/angie/docs/oss_changes/#angie
angie.software
https://altsp.su/obnovleniya-bezopasnosti/
altsp.su
and 21 more references View all →
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