CVE-2023-28807

Bypass of ZIA domain fronting detection module through evasion technique

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Published Jan 31, 2024 CVSS 3.1 · 5.1 Medium EPSS < 1% KEV · Not listed

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.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Zscaler

ZIA

unaffected

Version	Status	Constraints
`0`	affected	< 6.2r.290

Configuration 1 [-]

cpe:2.3:a:zscaler:secure_internet_and_saas_access:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
EUVD	EUVD-2023-32442	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.

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact Low

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.345% probability within 30 days)

Exploitation none

Automatable no

Technical Impact partial

References

Link	Providers
https://help.zscaler.com/zia/configuring-advanced-settings#dns-optimization
https://help.zscaler.com/zia/configuring-advanced-settings#domain-fronting

History

Jun 17, 2025 10:15 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Subscriptions

Zscaler Secure Internet And Saas Access

Weaknesses

CWE-295

Sources

CVE record Updated: Jun 17, 2025, 9:29 PM

Status: PUBLISHED
Assigner: Zscaler
Published: Jan 31, 2024, 7:16 PM
Updated: Jun 17, 2025, 9:29 PM
Reserved: Mar 23, 2023, 6:29 PM

View source JSON

Vulnrichment Updated: Aug 2, 2024, 1:51 PM

Updated: Aug 2, 2024, 1:51 PM

NVD Updated: Jun 17, 2026, 5:48 AM

Status: Modified
Published: Jan 31, 2024, 8:15 PM
Modified: Jun 17, 2026, 5:48 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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