High severity · published Nov 2, 2022
CVE-2022-26122
An insufficient verification of data authenticity vulnerability [CWE-345] in FortiClient, FortiMail and FortiOS AV engines version 6.2.168 and below and version 6.4.274 and below…
8.6
CVSS
0.5%
EPSS
No
On KEV
Description
An insufficient verification of data authenticity vulnerability [CWE-345] in FortiClient, FortiMail and FortiOS AV engines version 6.2.168 and below and version 6.4.274 and below may allow an attacker to bypass the AV engine via manipulating MIME attachment with junk and pad characters in base64.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 43% 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 6.0.15; 6.2.0 through 6.2.11; 6.4.0 through 6.4.10; 7.0.0 through 7.0.6; 7.2.0 · source: NVD
FA
Fortinet AV Engine, FortiMail, FortiOS, FortiClient · Fortinet
AV Engine version 6.2.168 and below and version 6.4.274 and below. · source: vendor
AE
Antivirus Engine · Fortinet
0.4.23; 2.0.49; 2.0.60; 4.4.54; 6.33; 6.137; +8 more · source: NVD
FO
Fortimail · Fortinet
6.0.0 through 6.0.12; 6.2.0 through 6.2.9; 6.4.0 through 6.4.6; 7.0.0 through 7.0.2; 4.1.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2022-26122
CVE.org
https://www.cve.org/CVERecord?id=CVE-2022-26122
Patch
https://fortiguard.com/psirt/FG-IR-22-074
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