CVE-2026-66729 (GCVE-0-2026-66729)
Vulnerability from cvelistv5 – Published: 2026-07-27 16:52 – Updated: 2026-07-31 18:19 X_Open Source
VLAI
EPSS
VEX
Title
facil.io 0.6.0 - 0.7.6 Integer Underflow DoS via Multipart MIME Body Parser
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.
Severity
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-27 17:54 UTC
CWE
- CWE-125 - Out-of-bounds Read
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://tpaidakis.com/writeups/facilio-parser-dos/ | technical-descriptionexploit |
| https://github.com/theopaid/Out-of-Bounds-Read-in… | technical-descriptionexploit |
| https://www.vulncheck.com/advisories/facil-io-int… | third-party-advisory |
Impacted products
Date Public
2026-07-24 00:00
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