CVE-2026-47079
Round-trip Corruption via Improper Entity Escaping in xml_builder
Description
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 <script> is emitted verbatim into the serialized XML rather than being escaped to &lt;script&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.
INFO
Published Date :
Aug. 21, 2026, 10:16 a.m.
Last Modified :
Aug. 21, 2026, 10:16 a.m.
Remotely Exploit :
No
Source :
6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Affected Products
The following products are affected by CVE-2026-47079
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | LOW | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | ||||
| CVSS 4.0 | LOW | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db |
Solution
- Update the xml_builder dependency to 2.4.1 or newer.
- Validate XML output for proper escaping.
- Ensure downstream parsers handle escaped data.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-47079.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-47079 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-47079
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-47079 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-47079 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Aug. 21, 2026
Action Type Old Value New Value Added Affected [{'cpes': ['cpe:2.3:a:joshnuss:xml_builder:*:*:*:*:*:*:*:*'], 'repo': 'https://github.com/joshnuss/xml_builder', 'vendor': 'joshnuss', 'modules': ["'Elixir.XmlBuilder'"], 'product': 'xml_builder', 'versions': [{'status': 'affected', 'version': '0.0.6', 'lessThan': '2.4.1', 'versionType': 'semver'}], 'packageURL': 'pkg:hex/xml_builder', 'packageName': 'xml_builder', 'programFiles': ['lib/xml_builder.ex'], 'collectionURL': 'https://repo.hex.pm', 'defaultStatus': 'unaffected', 'programRoutines': [{'name': "'Elixir.XmlBuilder':generate/1"}, {'name': "'Elixir.XmlBuilder':generate/2"}, {'name': "'Elixir.XmlBuilder':escape_string/1"}, {'name': "'Elixir.XmlBuilder':escape_entity/1"}]}, {'cpes': ['cpe:2.3:a:joshnuss:xml_builder:*:*:*:*:*:*:*:*'], 'repo': 'https://github.com/joshnuss/xml_builder', 'vendor': 'joshnuss', 'modules': ["'Elixir.XmlBuilder'"], 'product': 'xml_builder', 'versions': [{'status': 'affected', 'version': 'aae31e6e8ac837bcbb8afb816c0d14324b5cfe2b', 'lessThan': 'c3390e2046ec297b3bb8c30d5779cdfd6508c275', 'versionType': 'git'}], 'packageURL': 'pkg:github/joshnuss/xml_builder', 'packageName': 'joshnuss/xml_builder', 'programFiles': ['lib/xml_builder.ex'], 'collectionURL': 'https://github.com', 'defaultStatus': 'unaffected', 'programRoutines': [{'name': "'Elixir.XmlBuilder':generate/1"}, {'name': "'Elixir.XmlBuilder':generate/2"}, {'name': "'Elixir.XmlBuilder':escape_string/1"}, {'name': "'Elixir.XmlBuilder':escape_entity/1"}]}] Added Description 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 <script> is emitted verbatim into the serialized XML rather than being escaped to &lt;script&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. Added CVSS V4.0 AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-838 Added Reference https://cna.erlef.org/cves/CVE-2026-47079.html Added Reference https://github.com/joshnuss/xml_builder/commit/c3390e2046ec297b3bb8c30d5779cdfd6508c275 Added Reference https://github.com/joshnuss/xml_builder/security/advisories/GHSA-5hjx-8g53-cmvm Added Reference https://osv.dev/vulnerability/EEF-CVE-2026-47079