Raw 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/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:XSummary
CVE-2026-28808 is a high-severity Incorrect Authorization (CWE-863) vulnerability in Erlang Erlang\/Inets. Its CVSS base score is 8.3 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 43th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to AC-24 (Access Control Decisions) and AC-25 (Reference Monitor) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-28808 is an Incorrect Authorization vulnerability (CWE-863) in the inets modules of Erlang/OTP, specifically affecting the 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. The flaw arises when script_alias maps a URL prefix to a directory outside the 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 enables unauthenticated access to CGI scripts intended to be protected by directory rules. The vulnerability impacts Erlang/OTP versions from 17.0 up to but not including 28.4.2, 27.3.4.10, and 26.2.5.19, corresponding to inets versions from 5.10 up to but not including 9.6.2, 9.3.2.4, and 9.1.0.6. It has a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).
Any unauthenticated remote attacker can exploit this vulnerability over the network with low complexity and no user interaction required. By sending requests to CGI scripts exposed via script_alias configurations, attackers bypass directory-based authentication rules, gaining unauthorized execution of those scripts. Successful exploitation can result in high-impact confidentiality, integrity, and availability violations, potentially allowing arbitrary code execution, data exfiltration, or system compromise depending on the CGI scripts' privileges and functions.
Advisories and patches, detailed in sources such as the ERLEF CNA page, GitHub security advisory GHSA-3vhp-h532-mc3f, and specific commit fixes (8fc71ac6af4fbcc54103bec2983ef22e82942688 and 9dfa0c51eac97866078e808dec2183cb7871ff7c), recommend upgrading to remediated versions: OTP 28.4.2, 27.3.3.4.10, or 26.2.5.19 (with corresponding inets 9.6.2, 9.3.2.4, or 9.1.0.6). No workarounds are specified beyond avoiding script_alias for protected CGI scripts or reviewing configurations.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-19602
Vulnerability Data
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…
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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 28.4.2, OTP 27.3.4.10 and OTP 26.2.5.19, corresponding to inets from 5.10 before 9.6.2, 9.3.2.4 and 9.1.0.6.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 5 hardening rules · 3 OS baselines
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Mitigating Controls (NIST 800-53 r5) AI
AC-3 directly requires correct enforcement of authorization decisions on every access request, structurally preventing incorrect checks.
AC-24 ensures access-control decisions are made and applied consistently, reducing the chance of an incorrect authorization result.
A reference monitor that is always invoked and tamper-proof forces every authorization decision through a verified, correct path.
Least-privilege assignments shrink the set of authorizations that must be checked correctly, limiting exposure to flawed checks.
SI-10 mandates validation (including canonicalization) of inputs before security decisions are made, directly stopping the incorrect ordering that enables the bypass.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Defining, enforcing, and reviewing access authorizations and least privilege directly prevents incorrect authorization checks.
Secure SDLC practices directly require correct authorization logic after parsing/canonicalization to prevent bypasses.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can detect this weakness but does not prevent it by itself.
Requiring consistency between access rights and classification plus formal approval steps ensures that the authorization logic correctly distinguishes between entities that should and should not be granted access.
Enforcing policy-driven approval and role-change reviews stops incorrect or stale authorization decisions from remaining in effect after job changes or terminations.
Secure development lifecycle requires proper URL parsing and canonicalization before authorization checks.
Application security requirements should mandate correct authorization order after canonicalization.
Secure architecture principles include proper request handling order to prevent bypasses.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (2 rules)
- V-248581 OL 8 must require users to provide a password for privilege escalation. prevents CWE-863
- V-252656 The OL 8 operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-863
RHEL 7 (1 rule)
- V-204430 The Red Hat Enterprise Linux operating system must be configured so that users must re-authenticate for privilege escalation. prevents CWE-863
RHEL 8 (1 rule)
- V-251712 The RHEL 8 operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-863