CVE-2020-12819: fortios Heap Overflow — Fix

Description

A heap-based buffer overflow vulnerability in the processing of Link Control Protocol messages in FortiGate versions 5.6.12, 6.0.10, 6.2.4 and 6.4.1 and earlier may allow a remote attacker with valid SSL VPN credentials to crash the SSL VPN daemon by sending a large LCP packet, when tunnel mode is enabled. Arbitrary code execution may be theoretically possible, albeit practically very difficult to achieve in this context

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CVSS v3.1 Score

5.4

MEDIUM

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

Weakness Type (CWE)

CWE-122 CWE-122

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
fortinet	fortios	< 5.6.13
fortinet	fortios	6.0.0 — 6.0.11
fortinet	fortios	6.2.0 — 6.2.5
fortinet	fortios	6.4.0 — 6.4.2

References

Advisories & Patches

https://fortiguard.com/advisory/FG-IR-20-082

Frequently Asked Questions

What is CVE-2020-12819? +

A heap-based buffer overflow vulnerability in the processing of Link Control Protocol messages in FortiGate versions 5.6.12, 6.0.10, 6.2.4 and 6.4.1 and earlier may allow a remote attacker with valid SSL VPN credentials to crash the SSL VPN daemon by sending a large LCP packet, when tunnel mode is enabled. Arbitrary code execution may be theoretically possible, albeit practically very difficult to achieve in this context It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2020-12819? +

CVE-2020-12819 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2020-12819? +

CVE-2020-12819 affects products from fortinet, specifically: fortios. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2020-12819? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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