joshnuss xml_builder up to 2.4.0 lib/xml_builder.ex cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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4.1$0-$5k2.36

Summaryinfo

A vulnerability identified as problematic has been detected in joshnuss xml_builder up to 2.4.0. The affected element is the function XmlBuilder.generate/XmlBuilder.escape_string/XmlBuilder.escape_entity of the file lib/xml_builder.ex. This manipulation causes cross site scripting. This vulnerability is handled as CVE-2026-47079. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in joshnuss xml_builder up to 2.4.0. It has been declared as problematic. Affected by this vulnerability is the function XmlBuilder.generate/XmlBuilder.escape_string/XmlBuilder.escape_entity of the file lib/xml_builder.ex. The manipulation with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

Inappropriate Encoding for Output Context vulnerability in joshnuss xml_builder (XmlBuilder module) allows Content Spoofing, Cross-site Scripting. This vulnerability is associated with program files lib/xml_builder.ex and program routines XmlBuilder.generate/1, XmlBuilder.generate/2, XmlBuilder.escape_string/1, XmlBuilder.escape_entity/1. XmlBuilder.generate/1 does not escape literal & characters in text or attribute values when they are followed by an entity-like token (lt;, gt;, amp;, quot;, apos;). As a result, attacker-supplied input such as &lt;script&gt; is emitted verbatim into the serialized XML rather than being escaped to &amp;lt;script&amp;gt;. When a downstream XML parser later reads the document, it decodes the entity sequences into the literal characters <script>, promoting inert-looking text into real markup. This allows an attacker to bypass upstream filters that block raw < and > characters, injecting markup into any downstream consumer that parses the produced XML and renders the text content in a markup-sensitive context (HTML, SVG, RSS/Atom feeds). Both element text and attribute values are affected. This issue affects xml_builder: from 0.0.6 before 2.4.1.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-47079 since 05/18/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

Upgrading to version 2.4.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-63880). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

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Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔒
Status: Not defined
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: xml_builder 2.4.1

Timelineinfo

05/18/2026 CVE reserved
08/21/2026 +95 days Advisory disclosed
08/21/2026 +0 days VulDB entry created
08/21/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-47079 (🔒)
GCVE (CVE): GCVE-0-2026-47079
GCVE (VulDB): GCVE-100-394081
EUVD: 🔒

Entryinfo

Created: 08/21/2026 12:08
Updated: 08/21/2026 13:49
Changes: 08/21/2026 12:08 (68), 08/21/2026 13:49 (1)
Complete: 🔍
Cache ID: 216::103

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

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