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Vulnerability from bitnami_vulndb
Published
2026-03-27 07:10
Modified
2026-03-27 07:40
Summary
NGINX ngx_mail_auth_http_module vulnerability
Details
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.
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CVE-2026-27651 (GCVE-0-2026-27651)
Vulnerability from cvelistv5 – Published: 2026-03-24 14:13 – Updated: 2026-06-30 12:08
VLAI
EPSS
Title
NGINX ngx_mail_auth_http_module vulnerability
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-476 - NULL Pointer Dereference
Assigner
References
19 references
Impacted products
17 products
| Vendor | Product | Version | |
|---|---|---|---|
| F5 | NGINX Open Source |
Affected:
1.29.0 , < 1.29.7
(semver)
Affected: 0.5.15 , < 1.28.3 (semver) |
|
| F5 | NGINX Plus |
Affected:
R36 , < R36 P3
(custom)
Affected: R35 , < R35 P2 (custom) Affected: R34 , < * (custom) Affected: R33 , < * (custom) Affected: R32 , < R32 P5 (custom) |
|
| Red Hat | Red Hat Enterprise Linux AppStream EUS (v. 10.0) |
cpe:/o:redhat:enterprise_linux_eus:10.0 |
|
| Red Hat | Red Hat Enterprise Linux AppStream (v. 10) |
cpe:/o:redhat:enterprise_linux:10.1 |
|
| Red Hat | Red Hat Enterprise Linux AppStream (v. 8) |
cpe:/a:redhat:enterprise_linux:8::appstream |
|
| Red Hat | Red Hat Enterprise Linux AppStream E4S (v.9.0) |
cpe:/a:redhat:rhel_e4s:9.0::appstream |
|
| Red Hat | Red Hat Enterprise Linux AppStream E4S (v.9.2) |
cpe:/a:redhat:rhel_e4s:9.2::appstream |
|
| Red Hat | Red Hat Enterprise Linux AppStream EUS (v.9.4) |
cpe:/a:redhat:rhel_eus:9.4::appstream |
|
| Red Hat | Red Hat Enterprise Linux AppStream EUS (v.9.6) |
cpe:/a:redhat:rhel_eus:9.6::appstream |
|
| Red Hat | Red Hat Enterprise Linux AppStream (v. 9) |
cpe:/a:redhat:enterprise_linux:9::appstream |
|
| Red Hat | Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) |
cpe:/o:redhat:enterprise_linux_eus:10.0 |
|
| Red Hat | Red Hat CodeReady Linux Builder EUS (v.9.4) |
cpe:/a:redhat:rhel_eus:9.4::crb |
|
| Red Hat | Red Hat CodeReady Linux Builder EUS (v.9.6) |
cpe:/a:redhat:rhel_eus:9.6::crb |
|
| Red Hat | Red Hat Hardened Images |
cpe:/a:redhat:hummingbird:1 |
|
| Red Hat | Red Hat Update Infrastructure 5 |
cpe:/a:redhat:rhui:5::el9 |
|
| Red Hat | Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) |
cpe:/o:redhat:enterprise_linux:10.1 |
|
| Red Hat | Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) |
cpe:/a:redhat:enterprise_linux:9::crb |
Date Public
2026-03-24 14:00
Credits
F5 acknowledges Arkadi Vainbrand for bringing this issue to our attention and following the highest standards of coordinated disclosure.
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
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Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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