ZIA Admin Portal: Improper Verification of Cryptographic Signature
CVE-2023-28801 is a critical-severity improper verification of cryptographic signature vulnerability in ZIA Admin Portal from Zscaler, with a CVSS 3.1 base score of 9.8 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 6.2 (current) as the first without the flaw, so updating ZIA Admin Portal to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.39% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update ZIA Admin Portal to 6.2 (current) or a later version.
- Update Zscaler Internet Access Admin Portal to 6.2r or a later version.
- 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 | ZIA Admin Portal | 6.2 up to, but not including, 6.2 (current) | 6.2 (current) |
| Zscaler | Zscaler Internet Access Admin Portal | 6.2 up to, but not including, 6.2r | 6.2r |
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
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.6 | Critical | CNA (zscaler.com) |
| CVSS 3.1 | 9.8 | Critical | NVD |
Official description
An Improper Verification of Cryptographic Signature in the SAML authentication of the Zscaler Admin UI allows a Privilege Escalation.This issue affects Admin UI: from 6.2 before 6.2r.
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
Patches and release notes
- help.zscaler.com/zia/release-upgrade-summary-2023Release Notes
Recent Improper Verification of Cryptographic Signature vulnerabilities
- 7.8 High severity
- 8.8 High severity
- 8.8 High severity
- 7.5 High severity
- 7.5 High severity
- 9.8 Critical severity
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