{"id":"CVE-2026-42345","aliases":["EUVD-2026-28855","GHSA-jhqw-944x-xh94"],"status":"published","title":"FastGPT: Cloud metadata endpoint SSRF protection bypass via port specification, IPv6 mapping, hex/decimal IP encoding, and trailing dot","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 blocks cloud metadata endpoints using a fullUrl.startsWith() check against a hardcoded list. This check can be bypassed using at least 7 different URL encoding techniques, all of which resolve to the same cloud metadata service but do not match the blocklist patterns. Additionally, the broader private IP check (isInternalIPv4/isInternalIPv6) is disabled by default because CHECK_INTERNAL_IP defaults to false (not 'true'), so these bypasses reach the metadata endpoint without any further validation. At time of publication, there are no publicly available patches.","severity":{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00213,"percentile":0.11649,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-918"],"published":"2026-05-08T22:11:09Z","modified":"2026-10-28T03:00:39Z","products":[{"vendor":"labring","product":"fastgpt"}],"references":[{"url":"https://github.com/labring/FastGPT/security/advisories/GHSA-jhqw-944x-xh94","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42345.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42345","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-42345","title":"FastGPT: Cloud metadata endpoint SSRF protection bypass via port specification, IPv6 mapping, hex/decimal IP encoding, and trailing dot","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 blocks cloud metadata endpoints using a fullUrl.startsWith() check against a hardcoded list. This check can be bypassed using at least 7 different URL encoding techniques, all of which resolve to the same cloud metadata service but do not match the blocklist patterns. Additionally, the broader private IP check (isInternalIPv4/isInternalIPv6) is disabled by default because CHECK_INTERNAL_IP defaults to false (not 'true'), so these bypasses reach the metadata endpoint without any further validation. At time of publication, there are no publicly available patches.","status":"published","published":"2026-05-08T22:11:09.63Z","modified":"2026-05-13T17:47:03.507Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T13:40:12.486331Z"}],"euvd":[{"id":"EUVD-2026-28855","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 blocks cloud metadata endpoints using a fullUrl.startsWith() check against a hardcoded list. This check can be bypassed using at least 7 different URL encoding techniques, all of which resolve to the same cloud metadata service but do not match the blocklist patterns. Additionally, the broader private IP check (isInternalIPv4/isInternalIPv6) is disabled by default because CHECK_INTERNAL_IP defaults to false (not 'true'), so these bypasses reach the metadata endpoint without any further validation. At time of publication, there are no publicly available patches.","status":"published","published":"2026-05-08T22:11:09Z","modified":"2026-05-13T17:47:03Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T19:04:33.260537Z"}],"nvd":[{"id":"CVE-2026-42345","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 blocks cloud metadata endpoints using a fullUrl.startsWith() check against a hardcoded list. This check can be bypassed using at least 7 different URL encoding techniques, all of which resolve to the same cloud metadata service but do not match the blocklist patterns. Additionally, the broader private IP check (isInternalIPv4/isInternalIPv6) is disabled by default because CHECK_INTERNAL_IP defaults to false (not 'true'), so these bypasses reach the metadata endpoint without any further validation. At time of publication, there are no publicly available patches.","status":"published","published":"2026-05-08T23:16:37.32Z","modified":"2026-07-24T21:10:00.143Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T14:12:18.239974Z"}],"osv":[{"id":"CVE-2026-42345","title":"FastGPT: Cloud metadata endpoint SSRF protection bypass via port specification, IPv6 mapping, hex/decimal IP encoding, and trailing dot","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 blocks cloud metadata endpoints using a fullUrl.startsWith() check against a hardcoded list. This check can be bypassed using at least 7 different URL encoding techniques, all of which resolve to the same cloud metadata service but do not match the blocklist patterns. Additionally, the broader private IP check (isInternalIPv4/isInternalIPv6) is disabled by default because CHECK_INTERNAL_IP defaults to false (not 'true'), so these bypasses reach the metadata endpoint without any further validation. At time of publication, there are no publicly available patches.","status":"published","published":"2026-05-08T22:11:09.63Z","modified":"2026-10-28T03:00:39.703943862Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T15:45:04.117819Z"}]}}