NGINX ngx_mail_auth_http_module vulnerability_CVE-2026-27651

7.5 / 10

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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.

Basic Information

ID CVE-2026-27651

Source f5

Published Mar 24, 2026 at 14:13

Modified Mar 24, 2026 at 15:14

Affected Product

Vendor F5

Product NGINX Open Source

Version 1.29.0

Affected Versions F5 NGINX Open Source 1.29.0
F5 NGINX Open Source 0.5.15
F5 NGINX Plus R36
F5 NGINX Plus R35
F5 NGINX Plus R34
F5 NGINX Plus R33
F5 NGINX Plus R32

CWE Classification

CWE-476

References

my.f5.com /manage/s/article/K000160383

{
    "lastseen": "",
    "description": "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.",
    "published": "2026-03-24T14:13:27.295Z",
    "modified": "2026-03-24T15:14:13.220Z",
    "type": "cve",
    "title": "NGINX ngx_mail_auth_http_module vulnerability",
    "source": "f5",
    "references": "https://my.f5.com/manage/s/article/K000160383",
    "id": "CVE-2026-27651",
    "bulletinFamily": "",
    "cwe": [
        "CWE-476"
    ],
    "cvelist": null,
    "sourceData": "F5 NGINX Open Source 1.29.0\nF5 NGINX Open Source 0.5.15\nF5 NGINX Plus R36\nF5 NGINX Plus R35\nF5 NGINX Plus R34\nF5 NGINX Plus R33\nF5 NGINX Plus R32",
    "sourceHref": "",
    "cvss": {
        "score": 7.5,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "NGINX Open Source",
    "version": "1.29.0",
    "vendor": "F5",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}