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, OTP 28.5.0.6, and OTP 29.0.6, corresponding to inets from 5.10 before 9.3.2.7, 9.6.2.3, and 9.7.2. Whether OTP before OTP 17.0, corresponding to inets before 5.10, is affected is unknown.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Erlang | OTP | 17.0, 5.10 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | erlang | 1:29.0.6+dfsg-1 | — |
| Debian 13 | erlang | 1:27.3.4.1+dfsg-1+deb13u4 | — |
| Debian 12 | erlang | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | erlang | 1:27.3.4.6+dfsg-1ubuntu0.2 | USN-8901-1 |
| Ubuntu 24.04 LTS | erlang | 1:25.3.2.8+dfsg-1ubuntu4.8 | USN-8901-1 |
| Ubuntu 22.04 LTS | erlang | 1:24.2.1+dfsg-1ubuntu0.8 | USN-8901-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | erlang | 1:22.2.7+dfsg-1ubuntu0.5+esm3 | USN-8901-1 |
| Ubuntu Pro 18.04 LTS | erlang | 1:20.2.2+dfsg-1ubuntu2+esm4 | USN-8901-1 |
| Ubuntu Pro 16.04 LTS | erlang | 1:18.3-dfsg-1ubuntu3.1+esm4 | USN-8901-1 |
| Ubuntu Pro 14.04 LTS | erlang | 1:16.b.3-dfsg-1ubuntu2.2+esm3 | USN-8901-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | erlang27 +38 | 27.3.4.17-0.1.hum1 | RHSA-2026:62531 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | erlang | 26.2.5.21-6 | — |
Advisories 3
- WID-SEC-2026-3146 Erlang/OTP: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 2, 2026
- USN-8901-1 erlang vulnerabilities Ubuntu Security Notices (USN) · Oct 8, 2026
- RHSA-2026:62531 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Oct 2, 2026
References
- https://github.com/erlang/otp/security/advisories/GHSA-c3cq-q8x6-547g vendor-advisory
- EEF CNA record for CVE-2026-74994 related
- OSV record EEF-CVE-2026-74994 related
- Erlang/OTP version ordering
- Fix commit 6982e38 in erlang/otp patch
- Fix commit c5ccec8 in erlang/otp patch
- Fix commit 6101cb7 in erlang/otp patch