{"id":"CVE-2026-85738","state":"PUBLISHED","title":"TREK: SSRF Guard Bypass via IPv6 Transition Addresses (NAT64/6to4)","description":"TREK is a collaborative travel planner. Prior to 3.4.0, the checkSsrf logic in server/src/utils/ssrfGuard.ts does not recognize NAT64, 6to4, or Teredo IPv6 transition addresses that encode an IPv4 destination. An authenticated user who controls a DNS record can supply a URL whose AAAA result is a transition address embedding a private, loopback, or link-local IPv4 target, and isAlwaysBlocked and isPrivateNetwork classify the address as allowed. In a deployment that routes the applicable transition format, user-facing imports, webhooks, integrations, or plugin egress can reach internal services or cloud metadata and expose returned information. This issue is fixed in version 3.4.0.","publishedAt":"2026-09-24T18:09:31.268Z","updatedAt":"2026-09-28T14:51:56.222Z","severity":{"score":6.3,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["liketrek TREK"],"affected":[{"vendor":"liketrek","product":"TREK","versions":[{"version":"< 3.4.0","status":"affected"}]}],"references":["https://github.com/liketrek/TREK/security/advisories/GHSA-9hpq-mrpx-mcxg","https://github.com/liketrek/TREK/pull/1540","https://github.com/liketrek/TREK/commit/a2bd9be184a94997105ce190dad920c41e7b10df","https://github.com/liketrek/TREK/releases/tag/v3.4.0"],"weaknesses":["CWE-918"],"ingestedAt":"2026-10-29T20:13:15.269Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/85xxx/CVE-2026-85738.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-85738","state":"PUBLISHED","datePublished":"2026-09-24T18:09:31.268Z","dateUpdated":"2026-09-28T14:51:56.222Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-09-04T14:50:16.719Z"},"containers":{"cna":{"title":"TREK: SSRF Guard Bypass via IPv6 Transition Addresses (NAT64/6to4)","descriptions":[{"lang":"en","value":"TREK is a collaborative travel planner. Prior to 3.4.0, the checkSsrf logic in server/src/utils/ssrfGuard.ts does not recognize NAT64, 6to4, or Teredo IPv6 transition addresses that encode an IPv4 destination. An authenticated user who controls a DNS record can supply a URL whose AAAA result is a transition address embedding a private, loopback, or link-local IPv4 target, and isAlwaysBlocked and isPrivateNetwork classify the address as allowed. In a deployment that routes the applicable transition format, user-facing imports, webhooks, integrations, or plugin egress can reach internal services or cloud metadata and expose returned information. This issue is fixed in version 3.4.0."}],"affected":[{"vendor":"liketrek","product":"TREK","versions":[{"version":"< 3.4.0","status":"affected"}]}],"references":[{"url":"https://github.com/liketrek/TREK/security/advisories/GHSA-9hpq-mrpx-mcxg","name":"https://github.com/liketrek/TREK/security/advisories/GHSA-9hpq-mrpx-mcxg","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/liketrek/TREK/pull/1540","name":"https://github.com/liketrek/TREK/pull/1540","tags":["x_refsource_MISC"]},{"url":"https://github.com/liketrek/TREK/commit/a2bd9be184a94997105ce190dad920c41e7b10df","name":"https://github.com/liketrek/TREK/commit/a2bd9be184a94997105ce190dad920c41e7b10df","tags":["x_refsource_MISC"]},{"url":"https://github.com/liketrek/TREK/releases/tag/v3.4.0","name":"https://github.com/liketrek/TREK/releases/tag/v3.4.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.3,"baseSeverity":"MEDIUM","confidentialityImpact":"HIGH","integrityImpact":"NONE","privilegesRequired":"LOW","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-918","lang":"en","description":"CWE-918: Server-Side Request Forgery (SSRF)","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-09-24T18:09:31.268Z"},"source":{"advisory":"GHSA-9hpq-mrpx-mcxg","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/liketrek/TREK/security/advisories/GHSA-9hpq-mrpx-mcxg","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-28T14:51:50.053724Z","id":"CVE-2026-85738","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-28T14:51:56.222Z"}}]}}}