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.
Fix
Patch, vendor advisory and mitigation references on NVD 4
- https://cna.erlef.org/cves/CVE-2026-28808.html Mitigation, Vendor Advisory
- https://github.com/erlang/otp/commit/8fc71ac6af4fbcc54103bec2983ef22e82942688 Patch
- https://github.com/erlang/otp/commit/9dfa0c51eac97866078e808dec2183cb7871ff7c Patch
- https://osv.dev/vulnerability/EEF-CVE-2026-28808 Patch, Third Party Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 8.3 · erlangNVD modified 2026-10-26 22:10
Affected (CPE criteria) 2
cpe:2.3:a:erlang:erlang\/inets:*:*:*:*:*:*:*:*cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
References 10
- https://cna.erlef.org/cves/CVE-2026-28808.html Mitigation, Vendor Advisory
- https://github.com/erlang/otp/commit/07b8f441ca711f9812fad9e9115bab3c3aa92f79
- https://github.com/erlang/otp/commit/8fc71ac6af4fbcc54103bec2983ef22e82942688 Patch
- https://github.com/erlang/otp/commit/9dfa0c51eac97866078e808dec2183cb7871ff7c Patch
- https://github.com/erlang/otp/security/advisories/GHSA-3vhp-h532-mc3f Third Party Advisory
- https://osv.dev/vulnerability/EEF-CVE-2026-28808 Patch, Third Party Advisory
- https://www.erlang.org/doc/system/versions.html#order-of-versions Product
- https://access.redhat.com/security/cve/CVE-2026-28808
- https://bugzilla.redhat.com/show_bug.cgi?id=2455909
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-28808.json