Medium severity · published Jul 18, 2022
CVE-2021-42755
An integer overflow / wraparound vulnerability [CWE-190] in FortiSwitch 7.0.2 and below, 6.4.9 and below, 6.2.x, 6.0.x; FortiRecorder 6.4.2 and below, 6.0.10 and below; FortiOS…
4.3
CVSS
0.4%
EPSS
No
On KEV
Description
An integer overflow / wraparound vulnerability [CWE-190] in FortiSwitch 7.0.2 and below, 6.4.9 and below, 6.2.x, 6.0.x; FortiRecorder 6.4.2 and below, 6.0.10 and below; FortiOS 7.0.2 and below, 6.4.8 and below, 6.2.10 and below, 6.0.x; FortiProxy 7.0.0, 2.0.6 and below, 1.2.x, 1.1.x, 1.0.x; FortiVoiceEnterprise 6.4.3 and below, 6.0.10 and below dhcpd daemon may allow an unauthenticated and network adjacent attacker to crash the dhcpd deamon, resulting in potential denial of service.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 34% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
FortiOS · Fortinet
5.4.0; 5.4.1; 5.4.2; 5.4.3; 5.4.4; 5.4.5; +34 more · source: NVD
FO
Fortiproxy · Fortinet
1.0.0 through 1.0.7; 1.1.0 through 1.1.6; 1.2.0 through 1.2.13; 2.0.0 through 2.0.6; 7.0.0 · source: NVD
FF
Fortirecorder Firmware · Fortinet
6.0.0; 6.0.1; 6.0.2; 6.0.3; 6.0.4; 6.0.5; +8 more · source: NVD
FO
Fortiswitch · Fortinet
6.0.0 through 6.0.7; 6.2.0 through 6.2.7; 6.4.0 through 6.4.9; 7.0.0 through 7.0.2 · source: NVD
FO
Fortivoice · Fortinet
5.3.0; 5.3.1; 5.3.2; 5.3.3; 5.3.4; 5.3.5; +34 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-42755
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-42755
Patch
https://fortiguard.com/psirt/FG-IR-21-155
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