High severity · published Dec 19, 2024
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…
7.5
CVSS
0.8%
EPSS
No
On KEV
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
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 56% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
FortiOS · Fortinet
6.4.0 through 6.4.1; 6.2.0 through 6.2.4; 6.0.0 through 6.0.10; 5.6.0 through 5.6.12 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-12819
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-12819
Vendor Advisory
https://fortiguard.com/advisory/FG-IR-20-082
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