Critical severity · published Dec 8, 2021
CVE-2021-26109
An integer overflow or wraparound vulnerability in the memory allocator of SSLVPN in FortiOS before 7.0.1 may allow an unauthenticated attacker to corrupt control data on the heap…
9.8
CVSS
1.9%
EPSS
No
On KEV
Description
An integer overflow or wraparound vulnerability in the memory allocator of SSLVPN in FortiOS before 7.0.1 may allow an unauthenticated attacker to corrupt control data on the heap via specifically crafted requests to SSLVPN, resulting in potentially arbitrary code execution.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.9% · higher than 79% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
FortiOS · Fortinet
6.0.0 through 6.0.12; 6.2.0 through 6.2.9; 6.4.0 through 6.4.5; 7.0.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-26109
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-26109
Patch
https://fortiguard.com/advisory/FG-IR-21-049
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