CVE-2026-47080: CDATA Section Breakout via Unsanitised ]]> in xml_builder
Noroxi assessment
Priority: Monitor (action score 8/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.22% (FIRST EPSS).
- Someone with local access to the system can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: joshnuss xml_builder 2.4.1, bfb1ada071ccc1e384c30f782197ca5154106706.
Low priority for now. Upgrade to joshnuss xml_builder 2.4.1, bfb1ada071ccc1e384c30f782197ca5154106706 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
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.
- Published
- Aug 21, 2026
- Updated
- Oct 16, 2026
- EPSS
- 0.2% · 12th percentile
- CWE
- CWE-91
Report tools
Action score
8
Monitor
Low priority for now.
- CVSS
- 8 / 40 · 2.1 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.2%
CISA SSVC decision
- Exploitation
- proof of concept
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · EEF
- 2.1
- NVD has not scored this yet; the score shown is the CNA’s.
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
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Versions reported by the vendor
Affected version ranges reported by the assigning authority (EEF). Independent of NVD's CPE analysis and usually ahead of it.
joshnuss xml_builder
- 0.0.7 and later · before 2.4.1affected · semver
- 26766f884ed19adee1563522c7afb5f056a6f3b5 and later · before bfb1ada071ccc1e384c30f782197ca5154106706affected · git
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Hex | xml_builder | from 0.0.7 · before 2.4.1 | 2.4.1 |
Same product
joshnuss: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-48590Element and Attribute Names Injected Verbatim into XML Output in xml_builder8Monitor
- CVE-2026-47079Round-trip Corruption via Improper Entity Escaping in xml_builder8Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| joshnuss xml_builder | 2.4.1 | Vendor (CNA) |
| joshnuss xml_builder | bfb1ada071ccc1e384c30f782197ca5154106706 | Vendor (CNA) |
| Hex:xml_builder | 2.4.1 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- Peter Ullrichfinder
- Joshua Nussbaumremediation developer
- Jonatan Männchen / EEFcoordinator
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-485900 days apartElement and Attribute Names Injected Verbatim into XML Output in xml_builder8Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
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Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- Integrity
- Availability
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- X
Weakness class (CWE)
CWE-91 · XML Injection (aka Blind XPath Injection)CVSS vector
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
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
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Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (4 more)Show less
- github.com/joshnuss/xml_builder/commit/bfb1ada071ccc1e384c30f782197ca5154106706
- github.com/joshnuss/xml_builder/security/advisories/GHSA-67r9-hmxw-h595
- osv.dev/vulnerability/EEF-CVE-2026-47080
- vincent.vulcoord.net/score/?state=Not+Scored&year=2026&year=2025&assigned_to=88bc49d9-8ddd-4227-affc-a613e67abc4d&ordering=-published&cve=CVE-2026-47080
Vendor advisories and official records. Exploit/PoC links are deliberately left out.