Azure Active Directory Authentication Library Elevation of Privilege Vulnerability
Priority MEDIUM 45Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.0 · NVD. Fix status from CNA and GitHub.
Summary
An elevation of privilege vulnerability exists in Azure Active Directory Authentication Library On-Behalf-Of flow, in the way the library caches tokens. This vulnerability allows an authenticated attacker to perform actions in context of another user. The authenticated attacker can exploit this vulneraiblity by accessing a service configured for On-Behalf-Of flow that assigns incorrect tokens. This security update addresses the vulnerability by removing fallback cache look-up for On-Behalf-Of scenarios.
Why it matters now
EPSS 0.03799 90th percentileScored 2026-11-07
Fix Fixed ADAL.NET (Microsoft): publicationNuget 5.2.0 (Microsoft): publication+1 more product
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Microsoft | ADAL.NET | 5.0.0 to before publication | publication | Patch available | CNA |
| Microsoft | Nuget 5.2.0 | 5.0.0 to before publication | publication | Patch available | CNA |
| — | microsoft.identitymodel.clients.activedirectory (NuGet) | 5.0.0 to before 5.2.0 | 5.2.0 | Patch available | GHSA-xc6x-cq47-9chw |
- ADAL.NET VendorMicrosoft Affected 5.0.0 to before publication Fixed in publication Patch available CNA
- Nuget 5.2.0 VendorMicrosoft Affected 5.0.0 to before publication Fixed in publication Patch available CNA
- microsoft.identitymodel.clients.activedirectory (NuGet) Vendor— Affected 5.0.0 to before 5.2.0 Fixed in 5.2.0 Patch available GHSA-xc6x-cq47-9chw
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:microsoft:active_directory_authentication_library:*:*:*:*:*:.net:*:* | 5.0.5 to before 5.2.0 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:active_directory_authentication_library:5.0.0:preview:*:*:*:.net:*:* | 5.0.0 preview | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:active_directory_authentication_library:5.0.1:preview:*:*:*:.net:*:* | 5.0.1 preview | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:active_directory_authentication_library:5.0.2:preview:*:*:*:.net:*:* | 5.0.2 preview | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:active_directory_authentication_library:5.0.3:preview:*:*:*:.net:*:* | 5.0.3 preview | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:nuget:5.2.0:*:*:*:*:*:*:* | 5.2.0 | Vulnerable | Microsoft |
- cpe:2.3:a:microsoft:active_directory_authentication_library:*:*:*:*:*:.net:*:* Versions 5.0.5 to before 5.2.0 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:active_directory_authentication_library:5.0.0:preview:*:*:*:.net:*:* Versions 5.0.0 preview Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:active_directory_authentication_library:5.0.1:preview:*:*:*:.net:*:* Versions 5.0.1 preview Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:active_directory_authentication_library:5.0.2:preview:*:*:*:.net:*:* Versions 5.0.2 preview Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:active_directory_authentication_library:5.0.3:preview:*:*:*:.net:*:* Versions 5.0.3 preview Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:nuget:5.2.0:*:*:*:*:*:*:* Versions 5.2.0 Vulnerable ·Microsoft
Remediation
- Fix · CNA ADAL.NET (Microsoft) Fixed in publication
- Fix · CNA Nuget 5.2.0 (Microsoft) Fixed in publication
- Fix · GHSA-xc6x-cq47-9chw microsoft.identitymodel.clients.activedirectory (NuGet) Fixed in 5.2.0 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2019-1258
- 2026-10-03 Alias added: GHSA-xc6x-cq47-9chw
- 2026-10-31 EPSS moved to the 90th–95th percentile
References
Sources
- CVE-2019-1258 · CVE Program
- CVE-2019-1258 · NVD
- FIRST EPSS
- GHSA-xc6x-cq47-9chw · GitHub Advisory Database · CC BY 4.0
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