Client Connector: Improper Verification of Cryptographic Signature
CVE-2024-23456 is a high-severity improper verification of cryptographic signature vulnerability in Client Connector from Zscaler, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 4.2.0.190 as the first without the flaw, so updating Client Connector to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.23% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Client Connector to 4.2.0.190 or a later version.
- Read the advisory on help.zscaler.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Zscaler | Client Connector | before 4.2.0.190 | 4.2.0.190 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | CNA (zscaler.com) |
| CVSS 3.1 | 7.5 | High | NVD |
Official description
Anti-tampering can be disabled under certain conditions without signature validation. This affects Zscaler Client Connector <4.2.0.190 with anti-tampering enabled.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Verification of Cryptographic Signature
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
More Improper Verification of Cryptographic Signature vulnerabilities (CWE-347)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in Client Connector
- 7.5 High severity
- 8.1 High severity
- 8.1 High severity
- 9.1 Critical severity
- 8.8 High severity
- 8.4 High severity
Recent Improper Verification of Cryptographic Signature vulnerabilities
- 7.8 High severity
- 7.2 High severity
- 7.8 High severity
- 8.8 High severity
- 7.5 High severity
- 7.8 High severity
Spotted an error? Tell us.