How severe is CVE-2018-13383?

CVE-2018-13383 has a CVSS 3.1 base score of 4.3 (MEDIUM). EPSS estimates a 33.6% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2018-13383: Fortinet FortiOS and FortiProxy Out-of-bounds

CISA Known Exploited Vulnerabilities

Fortinet FortiOS and FortiProxy Out-of-bounds Write is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2022-01-10

Remediation due

2022-07-10

Ransomware

Known use

Required action
Apply updates per vendor instructions.

CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2018-13383

Description

A heap buffer overflow in Fortinet FortiOS 6.0.0 through 6.0.4, 5.6.0 through 5.6.10, 5.4.0 through 5.4.12, 5.2.14 and earlier and FortiProxy 2.0.0, 1.2.8 and earlier in the SSL VPN web portal may cause the SSL VPN web service termination for logged in users due to a failure to properly handle javascript href data when proxying webpages.

Severity

CVSS 3.1 · CNA4.3 MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

SSVC · CISA-ADP

Exploitationactive

Automatableno

Technical impactpartial

Affected Products

Vendor	Product	Affected versions
Fortinet	Fortinet FortiOS and FortiProxy	FortiOS 6.0.0 through 6.0.4, 5.6.0 through 5.6.10, 5.4.0 through 5.4.12, 5.2.14 and earlier, FortiProxy 2.0.0, 1.2.8 and earlier

References

2 Links

Other references

Record Details

Published

2019-05-29

Last updated

2025-10-21

Assigner (CNA)

fortinet

Credited to

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.