CVE-2020-12820 Memory corruption in FortiOS

What is CVE-2020-12820?

CVE-2020-12820 is a medium-severity memory corruption vulnerability in Fortinet Fortios, published on 19 Dec 2024. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

Under non-default configuration, a stack-based buffer overflow in FortiOS version 6.0.10 and below, version 5.6.12 and below may allow a remote attacker authenticated to the SSL VPN to crash the FortiClient NAC daemon (fcnacd) and potentially execute arbitrary code via requesting a large FortiClient file name. We are not aware of proof of concept code successfully achieving the latter.

Weakness: CWE-787, CWE-121

Which versions are affected by CVE-2020-12820?

It affects 1 product.

Products include Fortinet Fortios.

How do I fix CVE-2020-12820?

No fix has been published for CVE-2020-12820 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2020-12820 being exploited?

There is no known exploitation of CVE-2020-12820 in the wild and no public exploit code.

Other vulnerabilities in Fortinet Fortios

• CVE-2024-23113 Fortinet Multiple Products Format String Exploited Critical 9.8
• CVE-2022-40684 Fortinet Multiple Products Authentication Bypass Exploited Critical 9.8
• CVE-2024-55591 Fortinet FortiOS and FortiProxy Authentication Bypass Exploited Critical 9.6
• CVE-2024-21762 Fortinet FortiOS Out-of-Bound Write Exploited Critical 9.6
• CVE-2022-42475 Fortinet FortiOS Heap-Based Buffer Overflow Exploited Critical 9.3

All Fortinet Fortios vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-8hp7-6mr2-85pv.