CVE-2026-28753 (GCVE-0-2026-28753)
Vulnerability from cvelistv5
Published
2026-03-24 14:13
Modified
2026-03-24 15:24
Severity ?
3.7 (Low) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
6.3 (Medium) - CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
6.3 (Medium) - CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
VLAI Severity ?
EPSS score ?
CWE
- CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')
Summary
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_mail_smtp_module module due to the improper handling of CRLF sequences in DNS responses. This allows an attacker-controlled DNS server to inject arbitrary headers into SMTP upstream requests, leading to potential request manipulation. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
References
| URL | Tags | ||||
|---|---|---|---|---|---|
|
|||||
Impacted products
| Vendor | Product | Version | |||||||
|---|---|---|---|---|---|---|---|---|---|
| F5 | NGINX Open Source |
Version: 1.29.0 ≤ Version: 0.6.27 ≤ |
|||||||
|
|||||||||
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-28753",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-03-24T15:24:28.689685Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-03-24T15:24:34.995Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unknown",
"modules": [
"ngx_mail_proxy_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": "0.6.27",
"versionType": "semver"
}
]
},
{
"defaultStatus": "unknown",
"modules": [
"ngx_mail_proxy_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": "Asim Viladi Oglu Manizada"
},
{
"lang": "en",
"type": "reporter",
"value": "Colin Warren"
},
{
"lang": "en",
"type": "reporter",
"value": "Xiao Liu (Yunnan University)"
},
{
"lang": "en",
"type": "reporter",
"value": "Yuan Tan (UC Riverside)"
},
{
"lang": "en",
"type": "reporter",
"value": "Bird Liu (Lanzhou University)"
}
],
"datePublic": "2026-03-24T14:00:00.000Z",
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "NGINX Plus and NGINX Open Source have a vulnerability in the ngx_mail_smtp_module module due to the improper handling of CRLF sequences in DNS responses. This allows an attacker-controlled DNS server to inject arbitrary headers into SMTP upstream requests, leading to potential request manipulation. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated."
}
],
"value": "NGINX Plus and NGINX Open Source have a vulnerability in the ngx_mail_smtp_module module due to the improper handling of CRLF sequences in DNS responses. This allows an attacker-controlled DNS server to inject arbitrary headers into SMTP upstream requests, leading to potential request manipulation. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "HIGH",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 3.7,
"baseSeverity": "LOW",
"confidentialityImpact": "NONE",
"integrityImpact": "LOW",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
"version": "3.1"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
},
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "HIGH",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 6.3,
"baseSeverity": "MEDIUM",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "NONE",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "LOW",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-93",
"description": "CWE-93 Improper Neutralization of CRLF Sequences (\u0027CRLF Injection\u0027)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-03-24T14:49:49.169Z",
"orgId": "9dacffd4-cb11-413f-8451-fbbfd4ddc0ab",
"shortName": "f5"
},
"references": [
{
"tags": [
"vendor-advisory"
],
"url": "https://my.f5.com/manage/s/article/K000160367"
}
],
"source": {
"discovery": "EXTERNAL"
},
"title": "NGINX ngx_mail_proxy_module vulnerability",
"x_generator": {
"engine": "F5 SIRTBot v1.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "9dacffd4-cb11-413f-8451-fbbfd4ddc0ab",
"assignerShortName": "f5",
"cveId": "CVE-2026-28753",
"datePublished": "2026-03-24T14:13:26.107Z",
"dateReserved": "2026-03-18T16:06:38.435Z",
"dateUpdated": "2026-03-24T15:24:34.995Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-28753\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-03-24T15:24:28.689685Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-03-24T15:24:31.847Z\"}}], \"cna\": {\"title\": \"NGINX ngx_mail_proxy_module vulnerability\", \"source\": {\"discovery\": \"EXTERNAL\"}, \"credits\": [{\"lang\": \"en\", \"type\": \"reporter\", \"value\": \"Asim Viladi Oglu Manizada\"}, {\"lang\": \"en\", \"type\": \"reporter\", \"value\": \"Colin Warren\"}, {\"lang\": \"en\", \"type\": \"reporter\", \"value\": \"Xiao Liu (Yunnan University)\"}, {\"lang\": \"en\", \"type\": \"reporter\", \"value\": \"Yuan Tan (UC Riverside)\"}, {\"lang\": \"en\", \"type\": \"reporter\", \"value\": \"Bird Liu (Lanzhou University)\"}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 3.7, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"LOW\", \"vectorString\": \"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N\", \"integrityImpact\": \"LOW\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"HIGH\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"NONE\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}, {\"format\": \"CVSS\", \"cvssV4_0\": {\"Safety\": \"NOT_DEFINED\", \"version\": \"4.0\", \"Recovery\": \"NOT_DEFINED\", \"baseScore\": 6.3, \"Automatable\": \"NOT_DEFINED\", \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N\", \"providerUrgency\": \"NOT_DEFINED\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"HIGH\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"LOW\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"NONE\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"vendor\": \"F5\", \"modules\": [\"ngx_mail_proxy_module\"], \"product\": \"NGINX Open Source\", \"versions\": [{\"status\": \"affected\", \"version\": \"1.29.0\", \"lessThan\": \"1.29.7\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"0.6.27\", \"lessThan\": \"1.28.3\", \"versionType\": \"semver\"}], \"defaultStatus\": \"unknown\"}, {\"vendor\": \"F5\", \"modules\": [\"ngx_mail_proxy_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\": \"unknown\"}], \"datePublic\": \"2026-03-24T14:00:00.000Z\", \"references\": [{\"url\": \"https://my.f5.com/manage/s/article/K000160367\", \"tags\": [\"vendor-advisory\"]}], \"x_generator\": {\"engine\": \"F5 SIRTBot v1.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"NGINX Plus and NGINX Open Source have a vulnerability in the ngx_mail_smtp_module module due to the improper handling of CRLF sequences in DNS responses. This allows an attacker-controlled DNS server to inject arbitrary headers into SMTP upstream requests, leading to potential request manipulation. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"NGINX Plus and NGINX Open Source have a vulnerability in the ngx_mail_smtp_module module due to the improper handling of CRLF sequences in DNS responses. This allows an attacker-controlled DNS server to inject arbitrary headers into SMTP upstream requests, leading to potential request manipulation. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-93\", \"description\": \"CWE-93 Improper Neutralization of CRLF Sequences (\u0027CRLF Injection\u0027)\"}]}], \"providerMetadata\": {\"orgId\": \"9dacffd4-cb11-413f-8451-fbbfd4ddc0ab\", \"shortName\": \"f5\", \"dateUpdated\": \"2026-03-24T14:49:49.169Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-28753\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-03-24T15:24:34.995Z\", \"dateReserved\": \"2026-03-18T16:06:38.435Z\", \"assignerOrgId\": \"9dacffd4-cb11-413f-8451-fbbfd4ddc0ab\", \"datePublished\": \"2026-03-24T14:13:26.107Z\", \"assignerShortName\": \"f5\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…