{"id":"CVE-2025-53859","state":"PUBLISHED","title":"NGINX ngx_mail_smtp_module vulnerability","description":"NGINX Open Source and NGINX Plus have a vulnerability in the ngx_mail_smtp_module that might allow an unauthenticated attacker to over-read NGINX SMTP authentication process memory; as a result, the server side may leak arbitrary bytes sent in a request to the authentication server. This issue happens during the NGINX SMTP authentication process and requires the attacker to make preparations against the target system to extract the leaked data. The issue affects NGINX only if (1) it is built with the ngx_mail_smtp_module, (2) the smtp_auth directive is configured with method \"none,\" and (3) the authentication server returns the \"Auth-Wait\" response header.\n\n\n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","publishedAt":"2025-08-13T14:46:55.471Z","updatedAt":"2025-11-04T21:12:39.856Z","severity":{"score":6.3,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","source":"f5"},"assigner":"f5","products":["F5 NGINX Plus","F5 NGINX Open Source"],"affected":[{"vendor":"F5","product":"NGINX Plus","defaultStatus":"unknown","versions":[{"version":"R35","status":"unaffected","versionType":"custom"},{"version":"R34","status":"affected","lessThan":"R34 P2","versionType":"custom"},{"version":"R33","status":"affected","lessThan":"R33 P3","versionType":"custom"},{"version":"R32","status":"affected","lessThan":"R32 P3","versionType":"custom"},{"version":"R31","status":"affected","lessThan":"*","versionType":"custom"},{"version":"R30","status":"affected","lessThan":"*","versionType":"custom"}],"modules":["ngx_mail_smtp_module"]},{"vendor":"F5","product":"NGINX Open Source","defaultStatus":"unknown","versions":[{"version":"0.7","status":"affected","lessThan":"1.29.1","versionType":"custom"}],"modules":["ngx_mail_smtp_module"]}],"references":["https://my.f5.com/manage/s/article/K000152786","http://www.openwall.com/lists/oss-security/2025/08/13/5"],"weaknesses":["CWE-125"],"ingestedAt":"2026-10-29T20:09:31.862Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/53xxx/CVE-2025-53859.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-53859","state":"PUBLISHED","datePublished":"2025-08-13T14:46:55.471Z","dateUpdated":"2025-11-04T21:12:39.856Z","assignerShortName":"f5","assignerOrgId":"9dacffd4-cb11-413f-8451-fbbfd4ddc0ab","dateReserved":"2025-07-29T17:12:25.039Z"},"containers":{"cna":{"title":"NGINX ngx_mail_smtp_module vulnerability","descriptions":[{"lang":"en","value":"NGINX Open Source and NGINX Plus have a vulnerability in the ngx_mail_smtp_module that might allow an unauthenticated attacker to over-read NGINX SMTP authentication process memory; as a result, the server side may leak arbitrary bytes sent in a request to the authentication server. This issue happens during the NGINX SMTP authentication process and requires the attacker to make preparations against the target system to extract the leaked data. The issue affects NGINX only if (1) it is built with the ngx_mail_smtp_module, (2) the smtp_auth directive is configured with method \"none,\" and (3) the authentication server returns the \"Auth-Wait\" response header.\n\n\n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated."}],"affected":[{"vendor":"F5","product":"NGINX Plus","defaultStatus":"unknown","versions":[{"version":"R35","status":"unaffected","versionType":"custom"},{"version":"R34","status":"affected","lessThan":"R34 P2","versionType":"custom"},{"version":"R33","status":"affected","lessThan":"R33 P3","versionType":"custom"},{"version":"R32","status":"affected","lessThan":"R32 P3","versionType":"custom"},{"version":"R31","status":"affected","lessThan":"*","versionType":"custom"},{"version":"R30","status":"affected","lessThan":"*","versionType":"custom"}],"modules":["ngx_mail_smtp_module"]},{"vendor":"F5","product":"NGINX Open Source","defaultStatus":"unknown","versions":[{"version":"0.7","status":"affected","lessThan":"1.29.1","versionType":"custom"}],"modules":["ngx_mail_smtp_module"]}],"references":[{"url":"https://my.f5.com/manage/s/article/K000152786","tags":["vendor-advisory"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":3.7,"baseSeverity":"LOW","confidentialityImpact":"LOW","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","version":"3.1"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]},{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","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:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"NONE","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-125","description":"CWE-125 Out-of-bounds Read","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"f5","orgId":"9dacffd4-cb11-413f-8451-fbbfd4ddc0ab","dateUpdated":"2025-08-13T14:46:55.471Z"},"credits":[{"lang":"en","type":"reporter","value":"F5 acknowledges the Amazon Web Services Security team for bringing this issue to our attention and following the highest standards of coordinated disclosure."}],"datePublic":"2025-08-13T14:00:00.000Z","source":{"discovery":"EXTERNAL"},"x_generator":{"engine":"F5 SIRTBot v1.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2025-08-13T15:06:23.895538Z","id":"CVE-2025-53859","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-08-13T15:14:55.021Z"}},{"title":"CVE Program Container","references":[{"url":"http://www.openwall.com/lists/oss-security/2025/08/13/5"}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2025-11-04T21:12:39.856Z"}}]}}}