CVE-2024-23463Network attack vector

Anti-tampering bypass via Repair App race

Published Apr 30, 2024 · Updated Aug 29, 2024

TOCTOU race condition in Zscaler Client Connector before 4.2.1 on Windows allows remote authenticated users to bypass anti-tampering. During Repair App execution, the client checks a resource and later uses it after its state can change, invalidating the check; Zscaler has not identified that resource. The attacker needs low privileges and access to Repair App functionality; the documented consequence is limited to bypassing anti-tampering protection.

CVSS severity8.8
High
EPSS probability0.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

TOCTOU race condition in Zscaler Client Connector before 4.2.1 on Windows allows remote authenticated users to bypass anti-tampering. During Repair App execution, the client checks a resource and later uses it after its state can change, invalidating the check; Zscaler has not identified that resource. The attacker needs low privileges and access to Repair App functionality; the documented consequence is limited to bypassing anti-tampering protection.

The record

CVE
CVE-2024-23463
Published
Apr 30, 2024
Updated
Aug 29, 2024
Vendor
Zscaler
Product
Zscaler Client Connector
Classifications
CWE-367, CAPEC-554, T1687
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 30, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 29, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <4.2.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Zscaler · Zscaler Client Connectorversion=0 <4.2.1

Published CVSS scores

8.1NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
8.8Zscaler, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-367Time-of-check Time-of-use (TOCTOU) Race Condition
CAPEC-554Functionality Bypass
T1687Exploitation for Defense Impairment

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo