Medium severity · published May 4, 2022
CVE-2021-43206
A server-generated error message containing sensitive information in Fortinet FortiOS 7.0.0 through 7.0.3, 6.4.0 through 6.4.8, 6.2.x, 6.0.x and FortiProxy 7.0.0 through 7.0.1,…
4.3
CVSS
0.8%
EPSS
No
On KEV
Description
A server-generated error message containing sensitive information in Fortinet FortiOS 7.0.0 through 7.0.3, 6.4.0 through 6.4.8, 6.2.x, 6.0.x and FortiProxy 7.0.0 through 7.0.1, 2.0.x allows malicious webservers to retrieve a web proxy's client username and IP via same origin HTTP requests triggering proxy-generated HTTP status codes pages.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 57% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
FortiOS · Fortinet
5.6.0 before 6.0.14; 6.2.0 before 6.2.10; 6.4.0 before 6.4.8; 7.0.0 before 7.0.4 · source: NVD
FO
Fortiproxy · Fortinet
2.0.0 before 2.0.9; 7.0.0 before 7.0.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-43206
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-43206
Vendor Advisory
https://fortiguard.com/psirt/FG-IR-21-231
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