Zscaler Authentication Server prior 6.2r SAML Authentication signature verification

CVSS Meta Temp Score
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CTI Interest Score
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7.8$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Zscaler Authentication Server. This vulnerability affects unknown code of the component SAML Authentication. The manipulation leads to signature verification. This vulnerability is documented as CVE-2025-54982. The attack can be initiated remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Zscaler Authentication Server. It has been rated as critical. This issue affects some unknown functionality of the component SAML Authentication. The manipulation with an unknown input leads to a signature verification vulnerability. Using CWE to declare the problem leads to CWE-347. The product does not verify, or incorrectly verifies, the cryptographic signature for data. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

An improper verification of cryptographic signature in Zscaler's SAML authentication mechanism on the server-side allowed an authentication abuse.

The weakness was released by Richard Warren and Amberwolf. The advisory is shared at help.zscaler.com. The identification of this vulnerability is CVE-2025-54982 since 08/04/2025. The exploitation is known to be easy. The attack may be initiated remotely. Neither technical details nor an exploit are publicly available.

Upgrading to version 6.2r eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-23602). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.8

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.6
CNA Vector (Zscaler): 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Signature verification
CWE: CWE-347 / CWE-345
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Authentication Server 6.2r

Timelineinfo

08/04/2025 CVE reserved
08/05/2025 +1 days Advisory disclosed
08/05/2025 +0 days VulDB entry created
08/19/2025 +14 days VulDB entry last update

Sourcesinfo

Advisory: help.zscaler.com
Researcher: Richard Warren, Amberwolf
Status: Confirmed

CVE: CVE-2025-54982 (🔒)
GCVE (CVE): GCVE-0-2025-54982
GCVE (VulDB): GCVE-100-318761
EUVD: 🔒

Entryinfo

Created: 08/05/2025 09:16
Updated: 08/19/2025 12:13
Changes: 08/05/2025 09:16 (63), 08/05/2025 14:49 (1), 08/19/2025 12:13 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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