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TI-2026-47387 Aliases CVE-2026-66729GHSA-g2qx-6r8w-37px

facil.io 0.6.0 - 0.7.6 Integer Underflow DoS via Multipart MIME Body Parser

Priority HIGH 77CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-125 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00784 56th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by the CNA
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
boazsegevfacil.io0.6.0 – 0.7.6—No fix listedCNA
  • facil.io Vendorboazsegev Affected 0.6.0 – 0.7.6 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-66729
  2. 2026-10-03 Alias added: GHSA-g2qx-6r8w-37px

References

Exploit 2

  • TI-2026-47389 facil.io 0.7.5 - 0.7.6 HTTP/1.1 Chunked Transfer Encoding Parser Crash DoS CVSS 4.0HIGH 8.7
  • TI-2026-47388 facil.io 0.6.0 - 0.7.6 Infinite Loop DoS via Multipart MIME Body Parser CVSS 4.0HIGH 8.7
  • TI-2026-29774 Uncontrolled resource consumption in boazsegev facil.io CVSS 4.0HIGH 8.7
  • TI-2026-13899 boazsegev facil.io Public Folder http.c http_sendfile2 path traversal CVSS 4.0MEDIUM 6.9
  • TI-2026-13880 boazsegev facil.io WebSocket Frame websocket_parser.h websocket_on_protocol_error input validation CVSS 4.0MEDIUM 6.9
  • TI-2024-14668 Iodine Static File Server Path Traversal Vulnerability CVSS 3.1HIGH 7.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences