CVE-2026-27651 (GCVE-0-2026-27651)
Vulnerability from cvelistv5 – Published: 2026-03-24 14:13 – Updated: 2026-06-30 12:08
VLAI
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
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-27651",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "yes"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-03-24T15:02:03.137056Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-03-24T15:14:13.220Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
},
{
"affected": [
{
"cpes": [
"cpe:/o:redhat:enterprise_linux_eus:10.0"
],
"defaultStatus": "affected",
"product": "Red Hat Enterprise Linux AppStream EUS (v. 10.0)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:10.1"
],
"defaultStatus": "affected",
"product": "Red Hat Enterprise Linux AppStream (v. 10)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/a:redhat:enterprise_linux:8::appstream"
],
"defaultStatus": "affected",
"product": "Red Hat Enterprise Linux AppStream (v. 8)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/a:redhat:rhel_e4s:9.0::appstream"
],
"defaultStatus": "affected",
"product": "Red Hat Enterprise Linux AppStream E4S (v.9.0)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/a:redhat:rhel_e4s:9.2::appstream"
],
"defaultStatus": "affected",
"product": "Red Hat Enterprise Linux AppStream E4S (v.9.2)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/a:redhat:rhel_eus:9.4::appstream"
],
"defaultStatus": "affected",
"product": "Red Hat Enterprise Linux AppStream EUS (v.9.4)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/a:redhat:rhel_eus:9.6::appstream"
],
"defaultStatus": "affected",
"product": "Red Hat Enterprise Linux AppStream EUS (v.9.6)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/a:redhat:enterprise_linux:9::appstream"
],
"defaultStatus": "affected",
"product": "Red Hat Enterprise Linux AppStream (v. 9)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux_eus:10.0"
],
"defaultStatus": "affected",
"product": "Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/a:redhat:rhel_eus:9.4::crb"
],
"defaultStatus": "affected",
"product": "Red Hat CodeReady Linux Builder EUS (v.9.4)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/a:redhat:rhel_eus:9.6::crb"
],
"defaultStatus": "affected",
"product": "Red Hat CodeReady Linux Builder EUS (v.9.6)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/a:redhat:hummingbird:1"
],
"defaultStatus": "affected",
"product": "Red Hat Hardened Images",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/a:redhat:rhui:5::el9"
],
"defaultStatus": "affected",
"product": "Red Hat Update Infrastructure 5",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:10.1"
],
"defaultStatus": "unaffected",
"product": "Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)",
"vendor": "Red Hat"
},
{
"cpes": [
"cpe:/a:redhat:enterprise_linux:9::crb"
],
"defaultStatus": "unaffected",
"product": "Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)",
"vendor": "Red Hat"
}
],
"datePublic": "2026-03-24T14:13:27.295Z",
"descriptions": [
{
"lang": "en",
"value": "A flaw was found in NGINX, specifically within the ngx_mail_auth_http_module. When this module is enabled, and CRAM-MD5 or APOP authentication is active with an authentication server that permits retries, undisclosed requests can cause NGINX worker processes to terminate. This can lead to a Denial of Service (DoS), making the affected NGINX instance unavailable to legitimate users."
}
],
"metrics": [
{
"other": {
"content": {
"namespace": "https://access.redhat.com/security/updates/classification/",
"value": "Important"
},
"type": "Red Hat severity rating"
}
},
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"format": "CVSS"
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-476",
"description": "NULL Pointer Dereference",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-06-30T12:08:06.404Z",
"orgId": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"shortName": "redhat-SADP"
},
"references": [
{
"tags": [
"vdb-entry",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/security/cve/CVE-2026-27651"
},
{
"name": "RHBZ#2450791",
"tags": [
"issue-tracking",
"x_refsource_REDHAT"
],
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2450791"
},
{
"tags": [
"x_sadp-csaf-vex"
],
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27651.json"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:13634"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:6906"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:6907"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:15942"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:14836"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:13839"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:15943"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:15945"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:13680"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:15966"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:6923"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:7002"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:7343"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:8346"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:10065"
}
],
"solutions": [
{
"lang": "en",
"value": "RHSA-2026:13634: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)"
},
{
"lang": "en",
"value": "RHSA-2026:6906: Red Hat Enterprise Linux AppStream (v. 10)"
},
{
"lang": "en",
"value": "RHSA-2026:6907: Red Hat Enterprise Linux AppStream (v. 8)"
},
{
"lang": "en",
"value": "RHSA-2026:15942: Red Hat Enterprise Linux AppStream E4S (v.9.0)"
},
{
"lang": "en",
"value": "RHSA-2026:14836: Red Hat Enterprise Linux AppStream E4S (v.9.2)"
},
{
"lang": "en",
"value": "RHSA-2026:13839: Red Hat CodeReady Linux Builder EUS (v.9.4), Red Hat Enterprise Linux AppStream EUS (v.9.4)"
},
{
"lang": "en",
"value": "RHSA-2026:15943: Red Hat Enterprise Linux AppStream EUS (v.9.4)"
},
{
"lang": "en",
"value": "RHSA-2026:15945: Red Hat Enterprise Linux AppStream EUS (v.9.6)"
},
{
"lang": "en",
"value": "RHSA-2026:13680: Red Hat CodeReady Linux Builder EUS (v.9.6), Red Hat Enterprise Linux AppStream EUS (v.9.6)"
},
{
"lang": "en",
"value": "RHSA-2026:15966: Red Hat Enterprise Linux AppStream EUS (v.9.6)"
},
{
"lang": "en",
"value": "RHSA-2026:6923: Red Hat Enterprise Linux AppStream (v. 9)"
},
{
"lang": "en",
"value": "RHSA-2026:7002: Red Hat Enterprise Linux AppStream (v. 9)"
},
{
"lang": "en",
"value": "RHSA-2026:7343: Red Hat Enterprise Linux AppStream (v. 9)"
},
{
"lang": "en",
"value": "RHSA-2026:8346: Red Hat Hardened Images"
},
{
"lang": "en",
"value": "RHSA-2026:10065: Red Hat Update Infrastructure 5"
}
],
"timeline": [
{
"lang": "en",
"time": "2026-03-24T15:02:32.414Z",
"value": "Reported to Red Hat."
},
{
"lang": "en",
"time": "2026-03-24T14:13:27.295Z",
"value": "Made public."
}
],
"title": "NGINX: NGINX: Denial of Service via undisclosed requests when ngx_mail_auth_http_module is enabled",
"workarounds": [
{
"lang": "en",
"value": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability."
}
],
"x_adpType": "supplier",
"x_generator": {
"engine": "sadp-cli 1.0.0"
}
}
],
"cna": {
"affected": [
{
"defaultStatus": "unknown",
"modules": [
"ngx_mail_auth_http_module"
],
"product": "NGINX Open Source",
"vendor": "F5",
"versions": [
{
"lessThan": "1.29.7",
"status": "affected",
"version": "1.29.0",
"versionType": "semver"
},
{
"lessThan": "1.28.3",
"status": "affected",
"version": "0.5.15",
"versionType": "semver"
}
]
},
{
"defaultStatus": "unaffected",
"modules": [
"ngx_mail_auth_http_module"
],
"product": "NGINX Plus",
"vendor": "F5",
"versions": [
{
"lessThan": "R36 P3",
"status": "affected",
"version": "R36",
"versionType": "custom"
},
{
"lessThan": "R35 P2",
"status": "affected",
"version": "R35",
"versionType": "custom"
},
{
"lessThan": "*",
"status": "affected",
"version": "R34",
"versionType": "custom"
},
{
"lessThan": "*",
"status": "affected",
"version": "R33",
"versionType": "custom"
},
{
"lessThan": "R32 P5",
"status": "affected",
"version": "R32",
"versionType": "custom"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "reporter",
"value": "F5 acknowledges Arkadi Vainbrand for bringing this issue to our attention and following the highest standards of coordinated disclosure."
}
],
"datePublic": "2026-03-24T14:00:00.000Z",
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "\u003cspan style=\"background-color: rgb(255, 255, 255);\"\u003eWhen the \u003c/span\u003e\u003cstrong\u003engx_mail_auth_http_module\u003c/strong\u003e\u003cspan style=\"background-color: rgb(255, 255, 255);\"\u003e\u0026nbsp;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.\u003c/span\u003e Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated."
}
],
"value": "When the ngx_mail_auth_http_module\u00a0module 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."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
},
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"attackVector": "NETWORK",
"baseScore": 8.7,
"baseSeverity": "HIGH",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "HIGH",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "NONE",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-476",
"description": "CWE-476 NULL Pointer Dereference",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-03-24T14:22:35.756Z",
"orgId": "9dacffd4-cb11-413f-8451-fbbfd4ddc0ab",
"shortName": "f5"
},
"references": [
{
"tags": [
"vendor-advisory"
],
"url": "https://my.f5.com/manage/s/article/K000160383"
}
],
"source": {
"discovery": "EXTERNAL"
},
"title": "NGINX ngx_mail_auth_http_module vulnerability",
"x_generator": {
"engine": "F5 SIRTBot v1.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "9dacffd4-cb11-413f-8451-fbbfd4ddc0ab",
"assignerShortName": "f5",
"cveId": "CVE-2026-27651",
"datePublished": "2026-03-24T14:13:27.295Z",
"dateReserved": "2026-03-18T16:06:38.454Z",
"dateUpdated": "2026-06-30T12:08:06.404Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-27651",
"date": "2026-07-01",
"epss": "0.00921",
"percentile": "0.55881"
},
"nvd": "{\"cve\":{\"id\":\"CVE-2026-27651\",\"sourceIdentifier\":\"f5sirt@f5.com\",\"published\":\"2026-03-24T15:16:32.910\",\"lastModified\":\"2026-06-30T03:17:56.817\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"When the ngx_mail_auth_http_module\u00a0module 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.\"},{\"lang\":\"es\",\"value\":\"Cuando el m\u00f3dulo ngx_mail_auth_http_module est\u00e1 habilitado en NGINX Plus o NGINX Open Source, las solicitudes no reveladas pueden causar la terminaci\u00f3n de los procesos de trabajador. Este problema puede ocurrir cuando (1) la autenticaci\u00f3n CRAM-MD5 o APOP est\u00e1 habilitada, y (2) el servidor de autenticaci\u00f3n permite reintentar al devolver el encabezado de respuesta Auth-Wait. Nota: Las versiones de software que han alcanzado el Fin del Soporte T\u00e9cnico (EoTS) no son evaluadas.\"}],\"affected\":[{\"source\":\"f5sirt@f5.com\",\"affectedData\":[{\"vendor\":\"F5\",\"product\":\"NGINX Open Source\",\"defaultStatus\":\"unknown\",\"modules\":[\"ngx_mail_auth_http_module\"],\"versions\":[{\"version\":\"1.29.0\",\"lessThan\":\"1.29.7\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"0.5.15\",\"lessThan\":\"1.28.3\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"F5\",\"product\":\"NGINX Plus\",\"defaultStatus\":\"unaffected\",\"modules\":[\"ngx_mail_auth_http_module\"],\"versions\":[{\"version\":\"R36\",\"lessThan\":\"R36 P3\",\"versionType\":\"custom\",\"status\":\"affected\"},{\"version\":\"R35\",\"lessThan\":\"R35 P2\",\"versionType\":\"custom\",\"status\":\"affected\"},{\"version\":\"R34\",\"lessThan\":\"*\",\"versionType\":\"custom\",\"status\":\"affected\"},{\"version\":\"R33\",\"lessThan\":\"*\",\"versionType\":\"custom\",\"status\":\"affected\"},{\"version\":\"R32\",\"lessThan\":\"R32 P5\",\"versionType\":\"custom\",\"status\":\"affected\"}]}]},{\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"affectedData\":[{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux AppStream EUS (v. 10.0)\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux_eus:10.0\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux AppStream (v. 10)\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux:10.1\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux AppStream (v. 8)\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/a:redhat:enterprise_linux:8::appstream\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux AppStream E4S (v.9.0)\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/a:redhat:rhel_e4s:9.0::appstream\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux AppStream E4S (v.9.2)\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/a:redhat:rhel_e4s:9.2::appstream\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux AppStream EUS (v.9.4)\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/a:redhat:rhel_eus:9.4::appstream\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux AppStream EUS (v.9.6)\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/a:redhat:rhel_eus:9.6::appstream\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux AppStream (v. 9)\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/a:redhat:enterprise_linux:9::appstream\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux_eus:10.0\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat CodeReady Linux Builder EUS (v.9.4)\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/a:redhat:rhel_eus:9.4::crb\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat CodeReady Linux Builder EUS (v.9.6)\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/a:redhat:rhel_eus:9.6::crb\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Hardened Images\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/a:redhat:hummingbird:1\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Update Infrastructure 5\",\"defaultStatus\":\"affected\",\"cpes\":[\"cpe:/a:redhat:rhui:5::el9\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)\",\"defaultStatus\":\"unaffected\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux:10.1\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)\",\"defaultStatus\":\"unaffected\",\"cpes\":[\"cpe:/a:redhat:enterprise_linux:9::crb\"]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"f5sirt@f5.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X\",\"baseScore\":8.7,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"NONE\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"NONE\",\"vulnAvailabilityImpact\":\"HIGH\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"cvssMetricV31\":[{\"source\":\"f5sirt@f5.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6},{\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-03-24T15:02:03.137056Z\",\"id\":\"CVE-2026-27651\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"yes\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"f5sirt@f5.com\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-476\"}]},{\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-476\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"0.5.15\",\"versionEndIncluding\":\"0.9.7\",\"matchCriteriaId\":\"89573E06-4D65-4D4A-B9CD-7FD8AF637342\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"1.0.0\",\"versionEndExcluding\":\"1.28.3\",\"matchCriteriaId\":\"0E8049B1-4C36-4711-BB99-2721CF67FF81\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"1.29.0\",\"versionEndExcluding\":\"1.29.7\",\"matchCriteriaId\":\"C0EFE28B-E8E5-464E-B407-96436CA87C8E\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_plus:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"r33\",\"versionEndExcluding\":\"r35\",\"matchCriteriaId\":\"E7600A88-7651-4D8E-A04A-3AA81C850CC5\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_plus:r32:-:*:*:*:*:*:*\",\"matchCriteriaId\":\"36C4308E-651E-437C-84E7-10C542E3ADC2\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_plus:r32:p1:*:*:*:*:*:*\",\"matchCriteriaId\":\"FA913184-EAAD-409E-99C6-AB979DAA93F3\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_plus:r32:p2:*:*:*:*:*:*\",\"matchCriteriaId\":\"782DF180-1101-4D6A-A1D7-8DADBAF6D9D3\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_plus:r32:p3:*:*:*:*:*:*\",\"matchCriteriaId\":\"FB0B11F2-4748-492B-9906-F8C4C5EAFF12\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_plus:r32:p4:*:*:*:*:*:*\",\"matchCriteriaId\":\"86B53968-1CCA-4CF3-8454-BB92EF64D10E\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_plus:r35:-:*:*:*:*:*:*\",\"matchCriteriaId\":\"5D5FFD66-35C3-41AD-BD77-510E34A3AC6F\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_plus:r35:p1:*:*:*:*:*:*\",\"matchCriteriaId\":\"4958360C-7993-4C82-8685-202D4940CE01\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_plus:r36:-:*:*:*:*:*:*\",\"matchCriteriaId\":\"E7E5F940-048A-446F-9A1E-074612CEA1AC\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_plus:r36:p1:*:*:*:*:*:*\",\"matchCriteriaId\":\"7993A0FB-BE7E-4634-BF7F-FDEE3582D3E7\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:f5:nginx_plus:r36:p2:*:*:*:*:*:*\",\"matchCriteriaId\":\"862EA47E-8D57-434E-9C8F-238325FB85B2\"}]}]}],\"references\":[{\"url\":\"https://my.f5.com/manage/s/article/K000160383\",\"source\":\"f5sirt@f5.com\",\"tags\":[\"Vendor Advisory\"]},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:10065\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:13634\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:13680\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:13839\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:14836\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:15942\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:15943\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:15945\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:15966\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:6906\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:6907\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:6923\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:7002\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:7343\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:8346\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/security/cve/CVE-2026-27651\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://bugzilla.redhat.com/show_bug.cgi?id=2450791\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27651.json\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"}]}}",
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-27651\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-03-24T15:02:03.137056Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-03-24T15:14:09.900Z\"}}], \"cna\": {\"title\": \"NGINX ngx_mail_auth_http_module vulnerability\", \"source\": {\"discovery\": \"EXTERNAL\"}, \"credits\": [{\"lang\": \"en\", \"type\": \"reporter\", \"value\": \"F5 acknowledges Arkadi Vainbrand for bringing this issue to our attention and following the highest standards of coordinated disclosure.\"}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 7.5, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"NONE\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}, {\"format\": \"CVSS\", \"cvssV4_0\": {\"Safety\": \"NOT_DEFINED\", \"version\": \"4.0\", \"Recovery\": \"NOT_DEFINED\", \"baseScore\": 8.7, \"Automatable\": \"NOT_DEFINED\", \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N\", \"providerUrgency\": \"NOT_DEFINED\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"NONE\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"NONE\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"HIGH\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"vendor\": \"F5\", \"modules\": [\"ngx_mail_auth_http_module\"], \"product\": \"NGINX Open Source\", \"versions\": [{\"status\": \"affected\", \"version\": \"1.29.0\", \"lessThan\": \"1.29.7\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"0.5.15\", \"lessThan\": \"1.28.3\", \"versionType\": \"semver\"}], \"defaultStatus\": \"unknown\"}, {\"vendor\": \"F5\", \"modules\": [\"ngx_mail_auth_http_module\"], \"product\": \"NGINX Plus\", \"versions\": [{\"status\": \"affected\", \"version\": \"R36\", \"lessThan\": \"R36 P3\", \"versionType\": \"custom\"}, {\"status\": \"affected\", \"version\": \"R35\", \"lessThan\": \"R35 P2\", \"versionType\": \"custom\"}, {\"status\": \"affected\", \"version\": \"R34\", \"lessThan\": \"*\", \"versionType\": \"custom\"}, {\"status\": \"affected\", \"version\": \"R33\", \"lessThan\": \"*\", \"versionType\": \"custom\"}, {\"status\": \"affected\", \"version\": \"R32\", \"lessThan\": \"R32 P5\", \"versionType\": \"custom\"}], \"defaultStatus\": \"unaffected\"}], \"datePublic\": \"2026-03-24T14:00:00.000Z\", \"references\": [{\"url\": \"https://my.f5.com/manage/s/article/K000160383\", \"tags\": [\"vendor-advisory\"]}], \"x_generator\": {\"engine\": \"F5 SIRTBot v1.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"When the ngx_mail_auth_http_module\\u00a0module 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.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cspan style=\\\"background-color: rgb(255, 255, 255);\\\"\u003eWhen the \u003c/span\u003e\u003cstrong\u003engx_mail_auth_http_module\u003c/strong\u003e\u003cspan style=\\\"background-color: rgb(255, 255, 255);\\\"\u003e\u0026nbsp;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.\u003c/span\u003e Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-476\", \"description\": \"CWE-476 NULL Pointer Dereference\"}]}], \"providerMetadata\": {\"orgId\": \"9dacffd4-cb11-413f-8451-fbbfd4ddc0ab\", \"shortName\": \"f5\", \"dateUpdated\": \"2026-03-24T14:22:35.756Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-27651\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-03-24T15:14:13.220Z\", \"dateReserved\": \"2026-03-18T16:06:38.454Z\", \"assignerOrgId\": \"9dacffd4-cb11-413f-8451-fbbfd4ddc0ab\", \"datePublished\": \"2026-03-24T14:13:27.295Z\", \"assignerShortName\": \"f5\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
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 |
|---|
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.
Loading…
Loading…