CVE-2026-28808: Erlang OTP · Incorrect Authorization
Affects Erlang OTPSource CVE Database V5
Not known to be exploited · CVSS 8.3 High : upgrade to 26.2.5.19 soon.
Data as of 29 Oct 2026, 19:04 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 46% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 26.2.5.19, 9.1.0.6
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 7 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade OTP to 26.2.5.19; OTP and inets to 9.1.0.6.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| ErlangOTP | Affected
| Fixed in
|
| ErlangOTP | Affected
| Fixed in
|
| ErlangOTP | Affected
| Fixed in– |
GitHuberlang/otppkg:github/erlang/otpOther threats | Affected
| Fixed in– |
GitHubinetspkg:github/inetsOther threats | Affected
| Fixed in
|
CPE configurations (1)
cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
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Description
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.
References
- github.com/erlang/otp/security/advisories/GHSA-3vhp-h532-mc3f (opens in a new tab)
- cna.erlef.org/cves/CVE-2026-28808.html (opens in a new tab)
- osv.dev/vulnerability/EEF-CVE-2026-28808 (opens in a new tab)
- erlang.org/doc/system/versions.html (opens in a new tab)
- github.com/erlang/otp/commit/8fc71ac6af4fbcc54103bec2983ef22e82942688 (opens in a new tab)
- github.com/erlang/otp/commit/9dfa0c51eac97866078e808dec2183cb7871ff7c (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-28808 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2455909 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-28808.json (opens in a new tab)
- github.com/erlang/otp/commit/07b8f441ca711f9812fad9e9115bab3c3aa92f79 (opens in a new tab)