inets, httpd: Authentication Bypass via Directory Namespace Collapse in httpd mod_auth
Summary
| CVE | CVE-2026-74994 |
|---|---|
| State | PUBLISHED |
| Assigner | EEF |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-01 15:17:25 UTC |
| Updated | 2026-09-08 02:17:27 UTC |
| Description | The mod_auth module in OTP's inets httpd server, when configured with dets or mnesia authentication backends and multiple directory configuration blocks, collapses all directory blocks into a single shared user/group namespace. A user added to one protected directory is accepted as valid for all other protected directories on the same server instance. 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. |
Risk And Classification
Primary CVSS: v4.0 6 MEDIUM from 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS: 0.003640000 probability, percentile 0.293860000 (date 2026-09-03)
Problem Types: CWE-863 | CWE-1289 | CWE-863 CWE-863 Incorrect Authorization | CWE-1289 CWE-1289 Improper Validation of Unsafe Equivalence in Input
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | Secondary | 6 | MEDIUM | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | CVSS | 6 | MEDIUM | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
PresentPrivileges Required
LowUser Interaction
NoneConfidentiality
HighIntegrity
NoneAvailability
NoneSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Erlang | OTP | unknown 17.0 otp | Not specified |
| CNA | Erlang | OTP | affected 17.0 27.3.4.17 otp | Not specified |
| CNA | Erlang | OTP | affected 28.0 28.5.0.6 otp | Not specified |
| CNA | Erlang | OTP | affected 29.0 29.0.6 otp | Not specified |
| CNA | Erlang | OTP | unknown 5.10 otp | Not specified |
| CNA | Erlang | OTP | affected 5.10 9.3.2.7 otp | Not specified |
| CNA | Erlang | OTP | affected 9.4 9.6.2.3 otp | Not specified |
| CNA | Erlang | OTP | affected 9.7 9.7.2 otp | Not specified |
| CNA | Erlang | OTP | affected 84adefa331c4159d432d22840663c38f155cd4c1 * git | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/erlang/otp/commit/c5ccec8ed25c70ec6557fd81277e4b2f52285c19 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | |
| cna.erlef.org/cves/CVE-2026-74994.html | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | cna.erlef.org | |
| osv.dev/vulnerability/EEF-CVE-2026-74994 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | osv.dev | |
| github.com/erlang/otp/commit/6101cb74ff2870718c622ba7af0c100f7f2524e3 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | |
| github.com/erlang/otp/security/advisories/GHSA-c3cq-q8x6-547g | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | |
| github.com/erlang/otp/commit/6982e381137ede21a4e1faf5fa2dd82321691176 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Lukas Backström / Erlang Solutions (en)
CNA: Konrad Pietrzak (en)
There are currently no legacy QID mappings associated with this CVE.