Cyber Resilience

CVE-2018-13382

Access Control in Fortinet Fortios 5.4.1 – 5.4.11

CISA KEVActive ExploitationEUVD ExploitedRansomware-linkedAccess Control
Published
04 June 2019
Modified
24 October 2025
KEV Added
10 January 2022
Patch / advisory
View advisory
CVSS Score v3.1 9.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.82 99.6th percentile
Risk Priority 93 floored blend · peak EPSS

Summary

CVE-2018-13382 is a critical-severity Incorrect Authorization (CWE-863) vulnerability in Fortinet Fortios. Its CVSS base score is 9.1 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 0.4% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

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-2018-13382 is an improper authorization vulnerability, tracked under CWE-863, that affects the SSL VPN web portal in Fortinet FortiOS versions 6.0.0 through 6.0.4, 5.6.0 through 5.6.8, and 5.4.1 through 5.4.10, as well as FortiProxy versions 2.0.0, 1.2.0 through 1.2.8, 1.1.0 through 1.1.6, and 1.0.0 through 1.0.7. The flaw carries a CVSS v3.1 score of 9.1 and permits unauthorized changes to user credentials through the web portal interface.

An unauthenticated remote attacker can exploit the issue over the network by sending specially crafted HTTP requests to the SSL VPN web portal, enabling modification of an affected user's password. Successful exploitation grants the attacker the ability to change credentials without authentication, resulting in high impact to confidentiality and integrity while availability remains unaffected.

Official Fortinet advisories FG-IR-18-389 and FG-IR-20-231 address the vulnerability and are referenced alongside the CISA Known Exploited Vulnerabilities catalog entry, confirming active exploitation in the wild. Security practitioners should apply the patches or mitigations detailed in those advisories for the listed FortiOS and FortiProxy releases.

OWASP Top 10 for Web (2025)

A01:2025 Broken Access Control

EU & UK References

Vulnerability Data

An Improper Authorization vulnerability in Fortinet FortiOS 6.0.0 to 6.0.4, 5.6.0 to 5.6.8 and 5.4.1 to 5.4.10 and FortiProxy 2.0.0, 1.2.0 to 1.2.8, 1.1.0 to 1.1.6, 1.0.0 to 1.0.7 under SSL VPN web portal allows an unauthenticated attacker to modify…

more

the password of an SSL VPN web portal user via specially crafted HTTP requests

CWE(s)
CWE-863
KEV Date Added
10 January 2022

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
attack.mitre.org →
T1548.002 Bypass User Account Control Privilege Escalation
Adversaries may bypass UAC mechanisms to elevate process privileges on system.
attack.mitre.org →
T1548.003 Sudo and Sudo Caching Privilege Escalation
Adversaries may perform sudo caching and/or use the sudoers file to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2018-13383Same product: Fortinet Fortiosboth on KEV
CVE-2024-21762Same product: Fortinet Fortiosboth on KEV
CVE-2018-13379Same product: Fortinet Fortiosboth on KEV
CVE-2025-24472Same product: Fortinet Fortiosboth on KEV
CVE-2024-55591Same product: Fortinet Fortiosboth on KEV
CVE-2025-54822Same product: Fortinet Fortios
CVE-2022-40684Same product: Fortinet Fortiosboth on KEV
CVE-2023-36641Same product: Fortinet Fortios
CVE-2023-46718Same product: Fortinet Fortios
CVE-2023-41675Same product: Fortinet Fortios

Affected Assets

fortinet
fortiproxy
2.0.0 · ≤ 1.2.9
fortinet
fortios
5.4.1 — 5.4.11 · 5.6.0 — 5.6.9 · 6.0.0 — 6.0.5

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

—

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

AC-1 Policy and Procedures
addresses: CWE-863

Periodic review and update of procedures reduces incorrect authorization implementations over time.

AC-13 Supervision and Review — Access Control
addresses: CWE-863

Supervision identifies cases where authorization logic incorrectly permits unauthorized actions.

AC-16 Security and Privacy Attributes
addresses: CWE-863

Defining permitted attribute values and auditing modifications reduces the chance of incorrect authorization outcomes due to tampered or missing labels.

AC-17 Remote Access
addresses: CWE-863

The authorization process and usage restrictions help prevent incorrect authorization for remote access types.

AC-18 Wireless Access
addresses: CWE-863

Establishing configuration and connection requirements helps ensure correct rather than incorrect authorization for wireless access.

AC-19 Access Control for Mobile Devices
addresses: CWE-863

Establishing connection authorization processes for mobile devices helps ensure authorization decisions are correctly implemented rather than incorrect.

AC-2 Account Management
addresses: CWE-863

Monitoring account use, notifying on changes, and reviewing accounts for compliance corrects incorrect authorization assignments.

AC-20 Use of External Systems
addresses: CWE-863

Ensures authorization decisions for external system use are correctly implemented and enforced.

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.

PR.AA-05 mostly match
prevents

Defining, enforcing, and reviewing access authorizations and least privilege directly prevents incorrect authorization checks.

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.

A.5.15 Access control partial match
prevents

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.

A.5.18 Access rights partial match
prevents

Enforcing policy-driven approval and role-change reviews stops incorrect or stale authorization decisions from remaining in effect after job changes or terminations.

A.8.3 Information access restriction partial match
prevents

By tying access rights to identity, device, location and classification, the control reduces the likelihood that an authorization decision will be based on an incorrect or bypassed policy.

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

References