CVE-2026-66293
Received
Received - Intake
XML Injection in Saxy Encoder
Vulnerability report for CVE-2026-66293, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-06
Last updated on: 2026-11-06
Assigner: EEF
Description
Description
XML injection in the encoder of Saxy. Saxy.Encoder does not neutralize the -- sequence in XML comment content: escape_comment/2 returns the comment binary unchanged in every clause and only appends a space when the comment ends in a single -, so neither an interior -- nor a full --> is escaped or rejected before the encoder wraps the content in the <!-- and --> delimiters.
When an application serializes attacker-controlled text as a comment, through Saxy.XML.comment/1 or a raw {:comment, text} simple form child, the attacker can close the comment early with --> and inject arbitrary sibling markup into the serialized document. A downstream parser then sees elements, attributes, and text that the application never built. Where the document is rendered as HTML or SVG, the injected markup executes as stored cross-site scripting; where it is consumed by another XML processor, the attacker can forge data that the producing application never emitted. Documents that Saxy only parses are not a vector.
This issue affects saxy: from 0.7.0 before 1.7.0.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| 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. |