VDB-340850 · CVE-2026-21226 · EUVD-2026-2009

Microsoft Azure Core Shared Client Library for Python deserialization

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.8	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Microsoft Azure Core Shared Client Library for Python. It has been declared as critical. This issue affects some unknown processing. Such manipulation leads to deserialization. This vulnerability is referenced as CVE-2026-21226. It is possible to launch the attack remotely. No exploit is available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Microsoft Azure Core Shared Client Library for Python (version now known). Affected by this issue is some unknown processing. The manipulation with an unknown input leads to a deserialization vulnerability. Using CWE to declare the problem leads to CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Deserialization of untrusted data in Azure Core shared client library for Python allows an authorized attacker to execute code over a network.

The weakness was published 01/13/2026 as confirmed security update guide (Website). The advisory is available at msrc.microsoft.com. This vulnerability is handled as CVE-2026-21226. The exploitation is known to be difficult. The attack may be launched remotely. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 02/14/2026).

The vulnerability scanner Nessus provides a plugin with the ID 298922 (SUSE SLES15 / openSUSE 15 Security Update : python-azure-core (SUSE-SU-2026:0476-1)), which helps to determine the existence of the flaw in a target environment.

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (298922), EUVD (EUVD-2026-2009) and CERT Bund (WID-SEC-2026-0328). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

IBM App Connect Enterprise

Productinfo

Type

Cloud Software

Vendor

Microsoft

Name

Azure Core Shared Client Library for Python

License

commercial

Website

Vendor: https://www.microsoft.com/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 6.8

VulDB Base Score: 7.5
VulDB Temp Score: 6.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.5
Vendor Vector (Microsoft): 🔒

CNA Base Score: 7.5
CNA Vector (Microsoft): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Deserialization
CWE: CWE-502 / CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Unproven

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 298922
Nessus Name: SUSE SLES15 / openSUSE 15 Security Update : python-azure-core (SUSE-SU-2026:0476-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔒
0-Day Time: 🔒
Exposure Time: 🔒

Timelineinfo

01/13/2026 VulDB entry created
01/13/2026 +0 days Advisory disclosed
01/13/2026 +0 days Countermeasure disclosed
02/14/2026 +32 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2026-21226 (🔒)
GCVE (CVE): GCVE-0-2026-21226
GCVE (VulDB): GCVE-100-340850
EUVD: 🔒
CERT Bund: WID-SEC-2026-0328 - IBM App Connect Enterprise Certified Container: Mehrere Schwachstellen

Entryinfo

Created: 01/13/2026 20:01
Updated: 02/14/2026 23:00
Changes: 01/13/2026 20:01 (36), 01/13/2026 20:04 (33), 01/13/2026 23:38 (1), 01/21/2026 04:57 (11), 02/06/2026 12:02 (7), 02/14/2026 23:00 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.