CVE-2026-73270

Ein Angreifer kann mehrere Schwachstellen in Erlang/OTP ausnutzen, um Sicherheitsvorkehrungen zu umgehen, Daten zu manipulieren oder offenzulegen oder einen Denial-of-Service-Zustand auszulösen.

## Summary Improper Handling of Case Sensitivity vulnerability in Erlang/OTP inets httpd allows a remote unauthenticated attacker to read files inside a `mod_auth` protected directory by requesting them with different casing, on deployments whose filesystem is case-insensitive. `mod_auth:secret_path/3` decides whether a resolved filesystem path lies inside a protected `directory` block by running the configured directory path through `re:run/3` without the `caseless` option. A request for `/secret/file` against a directory configured as `/Secret` therefore does not match, so the request is treated as unprotected and no authentication challenge is issued, while the filesystem resolves the differently cased path to the same file and `mod_get` serves it. Deployments on case-sensitive filesystems are unaffected, because there the filesystem itself rejects the mismatched casing. This issue affects OTP from OTP 17.0 before OTP 27.3.4.17, from OTP 28.0 before OTP 28.5.0.6, and from OTP 29.0 before OTP 29.0.6, corresponding to inets from 5.10 before 9.3.2.7, from 9.4 before 9.6.2.3, and from 9.7 before 9.7.2. Whether OTP before OTP 17.0, corresponding to inets before 5.10, is affected is unknown. ## Workarounds * Host the document root on a case-sensitive filesystem, where the mismatched casing does not resolve to the protected file. * Place a reverse proxy in front of httpd that performs its own case-insensitive path matching for the protected paths, or that normalises request path casing before forwarding. * Restrict access to the server to trusted clients where the deployment allows it. ## Configurations Two conditions must both hold. The server must protect a directory with `mod_auth`, by configuring a `directory` block with authentication requirements, and the document root must sit where the operating system resolves paths case-insensitively, which is the default on Windows and on macOS. Deployments whose path resolution is case-sensitive are unaffected.