CVE-2026-47080
CDATA Section Breakout via Unsanitised ]]> in xml_builder
- Published
- Updated
- Reserved
- Assigned by
- EEF
Description
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.
Public exploit
A reference of the record is tagged as an exploit or proof of concept: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
Timeline
ID reserved
By EEF
- 3 months later
· 3 months later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| EEFCNA (assigner) | 4.0 | Low2.1 | CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N |
| NVDNVD · Awaiting Analysis | 4.0 | Low2.1 | CVSS:4.0/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 |
- EPSS (exploitation in 30 days)
- 0.22% · top 87% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 2.1.
Weakness
Affected products
- affected 0.0.7 – < 2.4.1
- affected 26766f884ed19adee1563522c7afb5f056a6f3b5 – < bfb1ada071ccc1e384c30f782197ca5154106706
References (5)
- https://github.com/joshnuss/xml_builder/security/advisories/GHSA-67r9-hmxw-h595 (opens in a new tab)vendor-advisoryrelated
- https://cna.erlef.org/cves/CVE-2026-47080.html (opens in a new tab)related
- https://osv.dev/vulnerability/EEF-CVE-2026-47080 (opens in a new tab)related
- https://github.com/joshnuss/xml_builder/commit/bfb1ada071ccc1e384c30f782197ca5154106706 (opens in a new tab)patch
- https://vincent.vulcoord.net/score/?state=Not+Scored&year=2026&year=2025&assigned_to=88bc49d9-8ddd-4227-affc-a613e67abc4d&ordering=-published&cve=CVE-2026-47080 (opens in a new tab)exploit
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-47080)Record last updated .