High severity · published Jan 31, 2024
CVE-2023-28807
Bypass of ZIA domain fronting detection module through evasion technique
7.5
CVSS
0.3%
EPSS
No
On KEV
Description
In Zscaler Internet Access (ZIA) a mismatch between Connect Host and Client Hello's Server Name Indication (SNI) enables attackers to evade network security controls by hiding their communications within legitimate traffic.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 28% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZI
ZIA · Zscaler
before 6.2r.290 · source: vendor
SI
Secure Internet And Saas Access · Zscaler
before 6.2r.290 · source: NVD