{"id":"CVE-2026-66729","aliases":["EUVD-2026-49358","GHSA-g2qx-6r8w-37px"],"status":"published","title":"facil.io 0.6.0 - 0.7.6 Integer Underflow DoS via Multipart MIME Body Parser","description":"facil.io 0.6.0 through 0.7.6 contains an integer underflow vulnerability in the multipart MIME body parser that allows unauthenticated remote attackers to crash the server process by sending a crafted Content-Disposition header with an empty field name. Attackers can trigger a uint32_t wraparound in http_mime_parser.h causing an out-of-bounds memory read past the name pointer, resulting in a bus fault that crashes the handling worker with a single POST request.","severity":{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00784,"percentile":0.56322,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":true,"fix_available":false},"cwes":["CWE-125"],"published":"2026-07-27T16:52:34Z","modified":"2026-10-28T02:30:53Z","exploits":[{"source":"pocgithub","id":"theopaid/CVE-2026-66729-Out-of-Bounds-Read-in-facil.io-MIME-Parser-leads-to-Server-Crash","title":"theopaid/CVE-2026-66729-Out-of-Bounds-Read-in-facil.io-MIME-Parser-leads-to-Server-Crash","date":"2026-07-24","url":"https://github.com/theopaid/CVE-2026-66729-Out-of-Bounds-Read-in-facil.io-MIME-Parser-leads-to-Server-Crash"}],"products":[{"vendor":"boazsegev","product":"facil.io"}],"references":[{"url":"https://tpaidakis.com/writeups/facilio-parser-dos/","tags":["technical-description","exploit","evidence"]},{"url":"https://github.com/theopaid/Out-of-Bounds-Read-in-facil.io-MIME-Parser-leads-to-Server-Crash","tags":["technical-description","exploit","evidence"]},{"url":"https://www.vulncheck.com/advisories/facil-io-integer-underflow-dos-via-multipart-mime-body-parser","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66729","tags":["advisory"]},{"url":"https://tpaidakis.com/writeups/facilio-parser-dos"},{"url":"https://github.com/advisories/GHSA-g2qx-6r8w-37px"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/66xxx/CVE-2026-66729.json","tags":["advisory"]},{"url":"https://github.com/boazsegev/facil.io","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-66729","title":"facil.io 0.6.0 - 0.7.6 Integer Underflow DoS via Multipart MIME Body Parser","description":"facil.io 0.6.0 through 0.7.6 contains an integer underflow vulnerability in the multipart MIME body parser that allows unauthenticated remote attackers to crash the server process by sending a crafted Content-Disposition header with an empty field name. Attackers can trigger a uint32_t wraparound in http_mime_parser.h causing an out-of-bounds memory read past the name pointer, resulting in a bus fault that crashes the handling worker with a single POST request.","status":"published","published":"2026-07-27T16:52:34.776Z","modified":"2026-07-31T18:19:06.846Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T14:20:12.939084Z"}],"euvd":[{"id":"EUVD-2026-49358","description":"facil.io 0.6.0 through 0.7.6 contains an integer underflow vulnerability in the multipart MIME body parser that allows unauthenticated remote attackers to crash the server process by sending a crafted Content-Disposition header with an empty field name. Attackers can trigger a uint32_t wraparound in http_mime_parser.h causing an out-of-bounds memory read past the name pointer, resulting in a bus fault that crashes the handling worker with a single POST request.","status":"published","published":"2026-07-27T16:52:34Z","modified":"2026-07-31T18:19:06Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T18:02:25.522444Z"}],"ghsa":[{"id":"GHSA-g2qx-6r8w-37px","title":"facil.io 0.6.0 through 0.7.6 contains an integer underflow vulnerability in the multipart MIME...","description":"facil.io 0.6.0 through 0.7.6 contains an integer underflow vulnerability in the multipart MIME body parser that allows unauthenticated remote attackers to crash the server process by sending a crafted Content-Disposition header with an empty field name. Attackers can trigger a uint32_t wraparound in http_mime_parser.h causing an out-of-bounds memory read past the name pointer, resulting in a bus fault that crashes the handling worker with a single POST request.","status":"published","published":"2026-07-27T18:31:49Z","modified":"2026-07-31T21:31:50Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T15:10:00.950607Z"}],"nvd":[{"id":"CVE-2026-66729","description":"facil.io 0.6.0 through 0.7.6 contains an integer underflow vulnerability in the multipart MIME body parser that allows unauthenticated remote attackers to crash the server process by sending a crafted Content-Disposition header with an empty field name. Attackers can trigger a uint32_t wraparound in http_mime_parser.h causing an out-of-bounds memory read past the name pointer, resulting in a bus fault that crashes the handling worker with a single POST request.","status":"published","published":"2026-07-27T17:16:42.517Z","modified":"2026-10-24T13:10:00.147Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T14:12:33.249634Z"}],"osv":[{"id":"CVE-2026-66729","title":"facil.io 0.6.0 - 0.7.6 Integer Underflow DoS via Multipart MIME Body Parser","description":"facil.io 0.6.0 through 0.7.6 contains an integer underflow vulnerability in the multipart MIME body parser that allows unauthenticated remote attackers to crash the server process by sending a crafted Content-Disposition header with an empty field name. Attackers can trigger a uint32_t wraparound in http_mime_parser.h causing an out-of-bounds memory read past the name pointer, resulting in a bus fault that crashes the handling worker with a single POST request.","status":"published","published":"2026-07-27T16:52:34.776Z","modified":"2026-10-28T02:30:53.942295573Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T15:45:14.46177Z"}]}}