CVE-2026-40606: mitmproxy has an LDAP Injection

April 14, 2026 (updated April 27, 2026)

In mitmproxy 12.2.1 and below, the builtin LDAP proxy authentication does not correctly sanitize the username when querying the LDAP server. This allows a malicious client to bypass authentication.

Only mitmproxy instances using the proxyauth option with LDAP are affected. This option is not enabled by default.

References

github.com/advisories/GHSA-527g-3w9m-29hv
github.com/mitmproxy/mitmproxy
github.com/mitmproxy/mitmproxy/security/advisories/GHSA-527g-3w9m-29hv
nvd.nist.gov/vuln/detail/CVE-2026-40606

Code Behaviors & Features

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