Improper Handling of Case Sensitivity in Erlang OTP - CVE-2026-73270
Published: September 2, 2026
Vulnerability identifier: #VU146836
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-73270
CWE-ID: CWE-178
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass authentication and access protected resources.
The vulnerability exists due to improper handling of case sensitivity in the mod_auth module in OTP\'s inets httpd server when processing requests for protected directory paths on case-insensitive filesystems. A remote attacker can request the same protected resource using different path casing to bypass authentication and access protected resources.
Only deployments on case-insensitive filesystems such as Windows and macOS are vulnerable, and exploitation requires one or more directory blocks configured with mod_auth.
Affected software
Erlang OTP
How to mitigate CVE-2026-73270
Install security update from vendor's website.
Erlang OTP - addressed in versions 17.0, 27.3.4.17, 28.5.0.6, 29.0.6