FKIE_CVE-2026-28753

Vulnerability from fkie_nvd - Published: 2026-03-24 15:16 - Updated: 2026-03-26 21:15
Severity ?
3.7 (Low) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
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
f5sirt@f5.comhttps://my.f5.com/manage/s/article/K000160367Vendor Advisory
Impacted products
Vendor Product Version
f5 nginx_plus r32
f5 nginx_plus r32
f5 nginx_plus r32
f5 nginx_plus r32
f5 nginx_plus r33
f5 nginx_plus r33
f5 nginx_plus r33
f5 nginx_plus r33
f5 nginx_plus r34
f5 nginx_plus r34
f5 nginx_plus r34
f5 nginx_plus r35
f5 nginx_plus r35
f5 nginx_plus r36
f5 nginx_plus r36
f5 nginx_plus r36
f5 nginx_open_source *
f5 nginx_open_source *
f5 nginx_open_source *
To clipboard 

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    },
    {
      "lang": "es",
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    }
  ],
  "id": "CVE-2026-28753",
  "lastModified": "2026-03-26T21:15:24.053",
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          "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",
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          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
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          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
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          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
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          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
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          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "LOW",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
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  "published": "2026-03-24T15:16:33.560",
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      "tags": [
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          "value": "CWE-93"
        }
      ],
      "source": "f5sirt@f5.com",
      "type": "Primary"
    }
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}


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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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Detection rules are retrieved from Rulezet.