{"api_version":"1","generated_at":"2026-07-11T03:51:21+00:00","cve":"CVE-2026-55187","urls":{"html":"https://cve.report/CVE-2026-55187","api":"https://cve.report/api/cve/CVE-2026-55187.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-55187","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-55187"},"summary":{"title":"Mailpit: Incomplete SSRF protection in Link Check API via IPv6 transition mechanisms (follow-up to CVE-2026-27808)","description":"Mailpit is an email testing tool and API for developers. Prior to 1.30.2, the remediation shipped for CVE-2026-27808 is incomplete because the tools.IsInternalIP deny-list in internal/tools/net.go relies on Go's standard library classification helpers and does not block IPv6 transition mechanisms or prefixes such as NAT64, 6to4, IPv4-compatible IPv6, ISATAP, fec0::/10, and 2001:db8::/32. An attacker who can deliver email and invoke POST /api/v1/message/{ID}/link-check can coerce the Link Check API's safeDialContext path into dialing internal destinations and can use status-code and error feedback to map internal service reachability, including cloud metadata endpoints. This issue is fixed in version 1.30.2.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-07-10 22:16:43","updated_at":"2026-07-10 22:16:43"},"problem_types":["CWE-918","CWE-918 CWE-918: Server-Side Request Forgery (SSRF)"],"metrics":[{"version":"3.1","source":"security-advisories@github.com","type":"Secondary","score":"5.8","severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N","baseScore":5.8,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"LOW","integrityImpact":"NONE","availabilityImpact":"NONE"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"5.8","severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N","data":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":5.8,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N","version":"3.1"}}],"references":[{"url":"https://github.com/axllent/mailpit/releases/tag/v1.30.2","name":"https://github.com/axllent/mailpit/releases/tag/v1.30.2","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/axllent/mailpit/security/advisories/GHSA-w4mc-hhc6-xp28","name":"https://github.com/axllent/mailpit/security/advisories/GHSA-w4mc-hhc6-xp28","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/axllent/mailpit/commit/a88dadbbe1df016a35a445089ef2a362a6c2de78","name":"https://github.com/axllent/mailpit/commit/a88dadbbe1df016a35a445089ef2a362a6c2de78","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-55187","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-55187","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"axllent","product":"mailpit","version":"affected < 1.30.2","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"product":"mailpit","vendor":"axllent","versions":[{"status":"affected","version":"< 1.30.2"}]}],"descriptions":[{"lang":"en","value":"Mailpit is an email testing tool and API for developers. 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This issue is fixed in version 1.30.2."}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":5.8,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-918","description":"CWE-918: Server-Side Request Forgery (SSRF)","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-07-10T21:43:59.548Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"references":[{"name":"https://github.com/axllent/mailpit/security/advisories/GHSA-w4mc-hhc6-xp28","tags":["x_refsource_CONFIRM"],"url":"https://github.com/axllent/mailpit/security/advisories/GHSA-w4mc-hhc6-xp28"},{"name":"https://github.com/axllent/mailpit/commit/a88dadbbe1df016a35a445089ef2a362a6c2de78","tags":["x_refsource_MISC"],"url":"https://github.com/axllent/mailpit/commit/a88dadbbe1df016a35a445089ef2a362a6c2de78"},{"name":"https://github.com/axllent/mailpit/releases/tag/v1.30.2","tags":["x_refsource_MISC"],"url":"https://github.com/axllent/mailpit/releases/tag/v1.30.2"}],"source":{"advisory":"GHSA-w4mc-hhc6-xp28","discovery":"UNKNOWN"},"title":"Mailpit: Incomplete SSRF protection in Link Check API via IPv6 transition mechanisms (follow-up to CVE-2026-27808)"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2026-55187","datePublished":"2026-07-10T21:43:59.548Z","dateReserved":"2026-06-16T15:20:43.086Z","dateUpdated":"2026-07-10T21:43:59.548Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-10 22:16:43","lastModifiedDate":"2026-07-10 22:16:43","problem_types":["CWE-918","CWE-918 CWE-918: Server-Side Request Forgery (SSRF)"],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N","baseScore":5.8,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"LOW","integrityImpact":"NONE","availabilityImpact":"NONE"},"exploitabilityScore":3.9,"impactScore":1.4}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"55187","Ordinal":"1","Title":"Mailpit: Incomplete SSRF protection in Link Check API via IPv6 t","CVE":"CVE-2026-55187","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"55187","Ordinal":"1","NoteData":"Mailpit is an email testing tool and API for developers. Prior to 1.30.2, the remediation shipped for CVE-2026-27808 is incomplete because the tools.IsInternalIP deny-list in internal/tools/net.go relies on Go's standard library classification helpers and does not block IPv6 transition mechanisms or prefixes such as NAT64, 6to4, IPv4-compatible IPv6, ISATAP, fec0::/10, and 2001:db8::/32. An attacker who can deliver email and invoke POST /api/v1/message/{ID}/link-check can coerce the Link Check API's safeDialContext path into dialing internal destinations and can use status-code and error feedback to map internal service reachability, including cloud metadata endpoints. This issue is fixed in version 1.30.2.","Type":"Description","Title":"Mailpit: Incomplete SSRF protection in Link Check API via IPv6 t"}]}}}