GHSA-63cx-g855-hvv4Medium▾ Sunlitmitmproxy binaries embed a vulnerable python-hyper/h2 dependency
▾ Sunlit zone — Low / medium · no exploitation signal
impact 27.5 · likelihood 0 · exploitation 0
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Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
Last analysed / modified upstream
mitmproxy 12.1.1 and below embed python-hyper/h2 ≤ v4.2.0, which has a gap in its HTTP/2 header validation. This enables request smuggling attacks when mitmproxy is in a configuration where it translates HTTP/2 to HTTP/1. For example, this affects reverse proxies to http:// backends. It does not affect mitmproxy's regular mode.
All users are encouraged to upgrade to mitmproxy 12.1.2, which includes a fixed version of h2.
More details about the vulnerability itself can be found at https://github.com/python-hyper/h2/security/advisories/GHSA-847f-9342-265h.
mitmproxy < 12.1.2Upgrade to a patched release:
mitmproxy 12.1.2Connected by shared product, vendor, weakness, or advisory.