Incorrect Authorization vulnerability in Erlang OTP (inets modules) allows unauthenticated access to CGI scripts protected by directory rules when served via script_alias. When script_alias maps a URL prefix to a directory outside DocumentRoot, mod_auth evaluates directory-based access controls against the DocumentRoot-relative path while mod_cgi executes the script at the ScriptAlias-resolved path. This path mismatch allows unauthenticated access to CGI scripts that directory rules were meant to protect. This vulnerability is associated with program files lib/inets/src/http_server/mod_alias.erl, lib/inets/src/http_server/mod_auth.erl, and lib/inets/src/http_server/mod_cgi.erl. This issue affects OTP from OTP 17.0 before OTP 26.2.5.19, OTP 27.3.4.10, and OTP 28.4.2, corresponding to inets from 5.10 before 9.1.0.6, 9.3.2.4, and 9.6.2. Whether OTP before OTP 17.0, corresponding to inets before 5.10, is affected is unknown.
https://osv.dev/vulnerability/EEF-CVE-2026-28808
https://github.com/erlang/otp/security/advisories/GHSA-3vhp-h532-mc3f
https://www.erlang.org/doc/system/versions.html#order-of-versions
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-28808.json
https://github.com/erlang/otp/commit/9dfa0c51eac97866078e808dec2183cb7871ff7c
https://github.com/erlang/otp/commit/8fc71ac6af4fbcc54103bec2983ef22e82942688
https://github.com/erlang/otp/commit/07b8f441ca711f9812fad9e9115bab3c3aa92f79
https://cna.erlef.org/cves/CVE-2026-28808.html
Published: 2026-04-07
Updated: 2026-09-08
Base Score: 10
Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C
Severity: Critical
Base Score: 9.8
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
Base Score: 8.3
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00049