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TI-2026-34682 Aliases CVE-2026-47080

CDATA Section Breakout via Unsanitised ]]> in xml_builder

Priority MEDIUM 44CWE-91Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

XML Injection vulnerability in joshnuss xml_builder (XmlBuilder module) allows Content Spoofing, XML Injection. This vulnerability is associated with program files lib/xml_builder.ex and program routines XmlBuilder.generate/1, XmlBuilder.generate/2, XmlBuilder.escape/1. The escape/1 clause for {:cdata, data} in lib/xml_builder.ex concatenates data verbatim between the CDATA opener <![CDATA[ and closer ]]> without rewriting or splitting on the embedded ]]> sequence. Because CDATA sections have no internal escape mechanism, the only safe way to embed arbitrary bytes is to split on ]]> and emit adjacent CDATA sections. An attacker who can supply input containing ]]> closes the CDATA section early; any bytes that follow are parsed as ordinary XML markup by downstream consumers, allowing injection of arbitrary elements, text, or entity references into the output document. This issue affects xml_builder: from 0.0.7 before 2.4.1.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00222 12th percentileScored 2026-11-07
Fix Fixed xml_builder (joshnuss): 2.4.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
joshnussxml_builder0.0.7 to before 2.4.12.4.1Patch availableCNA
  • xml_builder Vendorjoshnuss Affected 0.0.7 to before 2.4.1 Fixed in 2.4.1 Patch available CNA

CPE names CNA · 1

CPEVersionsRoleVendor
cpe:2.3:a:joshnuss:xml_builder:*:*:*:*:*:*:*:*——joshnuss
  • cpe:2.3:a:joshnuss:xml_builder:*:*:*:*:*:*:*:* Versions — — ·joshnuss

Remediation

  • Fix · CNA xml_builder (joshnuss) Fixed in 2.4.1

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    joshnuss xml_builder 2.4.1

    3 records Highest priority Priority MEDIUM 3 MEDIUM

    Other records, highest priority first

    • TI-2026-35946 Element and Attribute Names Injected Verbatim into XML Output in xml_builderPriority MEDIUM 44
    • TI-2026-34681 Round-trip Corruption via Improper Entity Escaping in xml_builderPriority MEDIUM 44
    Show all 3 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-47080

References

Patch 1

Advisory 1

Other 2

  • TI-2026-35946 Element and Attribute Names Injected Verbatim into XML Output in xml_builder CVSS 4.0LOW 2.1
  • TI-2026-34681 Round-trip Corruption via Improper Entity Escaping in xml_builder CVSS 4.0LOW 2.1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences