NaturalIntelligence fast-xml-builder up to 1.1.6 attribute xml injection

CVSS Meta Temp Score
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CTI Interest Score
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6.6$0-$5k0.00

Summaryinfo

A vulnerability was found in NaturalIntelligence fast-xml-builder up to 1.1.6. It has been classified as critical. This vulnerability affects unknown code. The manipulation of the argument attribute leads to xml injection. This vulnerability is documented as CVE-2026-44665. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in NaturalIntelligence fast-xml-builder up to 1.1.6 and classified as critical. This issue affects an unknown code block. The manipulation of the argument attribute with an unknown input leads to a xml injection vulnerability. Using CWE to declare the problem leads to CWE-91. The product does not properly neutralize special elements that are used in XML, allowing attackers to modify the syntax, content, or commands of the XML before it is processed by an end system. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

fast-xml-builder builds XML from JSON. Prior to 1.1.7, when an input data has quotes in attribute values but process entities is not enabled, it breaks the attribute value into multiple attributes. This gives the room for an attacker to insert unwanted attributes to the XML/HTML. This vulnerability is fixed in 1.1.7.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-44665 since 05/07/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1505 for this issue.

Upgrading to version 1.1.7 eliminates this vulnerability.

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

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.7
VulDB Meta Temp Score: 6.6

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.1
CNA Vector (GitHub_M): 🔒

CVSSv2info

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

Exploitinginfo

Class: Xml injection
CWE: CWE-91 / CWE-74 / CWE-707
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: fast-xml-builder 1.1.7

Timelineinfo

05/07/2026 CVE reserved
05/13/2026 +6 days Advisory disclosed
05/13/2026 +0 days VulDB entry created
05/13/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-44665 (🔒)
GCVE (CVE): GCVE-0-2026-44665
GCVE (VulDB): GCVE-100-363641

Entryinfo

Created: 05/13/2026 18:25
Changes: 05/13/2026 18:25 (64)
Complete: 🔍
Cache ID: 216::103

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

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