{"id":"CVE-2026-42344","state":"PUBLISHED","title":"FastGPT: DNS rebinding TOCTOU bypass in isInternalAddress allows SSRF on all protected endpoints","description":"FastGPT is an AI Agent building platform. In versions 4.14.11 and prior, FastGPT's isInternalAddress() function in packages/service/common/system/utils.ts is vulnerable to DNS rebinding (TOCTOU — Time-of-Check to Time-of-Use). The function resolves the hostname via dns.resolve4()/dns.resolve6() and checks resolved IPs against private ranges, but the actual HTTP request happens in a separate call with a new DNS resolution, allowing the DNS record to change between validation and fetch. At time of publication, there are no publicly available patches.","publishedAt":"2026-05-08T22:10:00.875Z","updatedAt":"2026-05-11T18:03:27.685Z","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":["labring FastGPT"],"affected":[{"vendor":"labring","product":"FastGPT","versions":[{"version":"<= 4.14.11","status":"affected"}]}],"references":["https://github.com/labring/FastGPT/security/advisories/GHSA-cc8x-jrqv-hmwh"],"weaknesses":["CWE-367"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/42xxx/CVE-2026-42344.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-42344","state":"PUBLISHED","datePublished":"2026-05-08T22:10:00.875Z","dateUpdated":"2026-05-11T18:03:27.685Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-04-26T13:26:14.515Z"},"containers":{"cna":{"title":"FastGPT: DNS rebinding TOCTOU bypass in isInternalAddress allows SSRF on all protected endpoints","descriptions":[{"lang":"en","value":"FastGPT is an AI Agent building platform. In versions 4.14.11 and prior, FastGPT's isInternalAddress() function in packages/service/common/system/utils.ts is vulnerable to DNS rebinding (TOCTOU — Time-of-Check to Time-of-Use). The function resolves the hostname via dns.resolve4()/dns.resolve6() and checks resolved IPs against private ranges, but the actual HTTP request happens in a separate call with a new DNS resolution, allowing the DNS record to change between validation and fetch. At time of publication, there are no publicly available patches."}],"affected":[{"vendor":"labring","product":"FastGPT","versions":[{"version":"<= 4.14.11","status":"affected"}]}],"references":[{"url":"https://github.com/labring/FastGPT/security/advisories/GHSA-cc8x-jrqv-hmwh","name":"https://github.com/labring/FastGPT/security/advisories/GHSA-cc8x-jrqv-hmwh","tags":["x_refsource_CONFIRM"]}],"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-367","lang":"en","description":"CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-05-08T22:10:00.875Z"},"source":{"advisory":"GHSA-cc8x-jrqv-hmwh","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/labring/FastGPT/security/advisories/GHSA-cc8x-jrqv-hmwh","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-11T18:03:09.390132Z","id":"CVE-2026-42344","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":"2026-05-11T18:03:27.685Z"}}]}}}