Vulnerability Description
Inefficient Algorithmic Complexity vulnerability in elixir-mint mint allows a remote HTTP server to exhaust CPU on the client host and cause a denial of service. parse_hex_prefix/2 in lib/mint/http1/parse.ex folds each hex digit of a chunked response's chunk-size field into an arbitrary-precision accumulator with acc * 16 + digit and imposes no limit on the digit count. Because the accumulator grows without bound, the multiplication is not constant time and one pass over N digits costs O(N squared). handle_data/2 prepends conn.buffer and re-parses from the start on every socket message, so a server that dribbles the digits out in small packets makes the client pay that cost repeatedly. A run of roughly 512,000 hex digits costs over ten seconds of CPU in a single pass, measured on stock defaults. The parser reaches this state after a valid status line and a complete, valid header section, so an intermediary inspecting only headers sees an ordinary 200 response. This issue affects mint: from 1.9.3 before 1.10.0.
Related Weaknesses (CWE)
References
- https://cna.erlef.org/cves/CVE-2026-82729.html
- https://github.com/elixir-mint/mint/commit/bd2a4e7513594997c140cfef9fe0e968712fb
- https://github.com/elixir-mint/mint/security/advisories/GHSA-7p8w-j234-7qc8
- https://osv.dev/vulnerability/EEF-CVE-2026-82729
- https://github.com/elixir-mint/mint/security/advisories/GHSA-7p8w-j234-7qc8
FAQ
What is CVE-2026-82729?
CVE-2026-82729 is a documented vulnerability. Inefficient Algorithmic Complexity vulnerability in elixir-mint mint allows a remote HTTP server to exhaust CPU on the client host and cause a denial of service. parse_hex_prefix/2 in lib/mint/http1/...
How severe is CVE-2026-82729?
CVSS scoring is not yet available for CVE-2026-82729. Check NVD for updates.
Is there a patch for CVE-2026-82729?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.