fast-xml-builder: Comment Value bypass regex
Priority LOW 27CWE-91Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Partial Red Hat: 1 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat.
Summary
fast-xml-builder builds XML from JSON. In 1.1.5, the fix for CVE-2026-41650 in fast-xml-parser sanitizes -- sequences in XML comment content using .replace(/--/g, '- -'). This skip the values containing three consecutive dashes (e.g., --->...), allowing an attacker to break out of an XML comment and inject arbitrary XML/HTML content. This vulnerability is fixed in 1.1.6.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00194 9th percentileScored 2026-11-07
Fix Partial fast-xml-builder (npm): 1.1.6Red Hat: 1 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- 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
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| NaturalIntelligence | fast-xml-builder | 1.1.5 | — | No fix listed | CNA |
| — | fast-xml-builder (npm) | 1.1.5 to before 1.1.6 | 1.1.6 | Patch available | GHSA-45c6-75p6-83cc |
- fast-xml-builder VendorNaturalIntelligence Affected 1.1.5 Fixed in — No fix listed CNA
- fast-xml-builder (npm) Vendor— Affected 1.1.5 to before 1.1.6 Fixed in 1.1.6 Patch available GHSA-45c6-75p6-83cc
Remediation
- Fix · GHSA-45c6-75p6-83cc fast-xml-builder (npm) Fixed in 1.1.6 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Self-service automation portal 2 | Affected | No fix yet: Fix deferred |
Not affected: 4 products
- Red Hat Advanced Cluster Security 4
- Red Hat Developer Hub 1
- Red Hat OpenShift Virtualization 4
- Red Hat Openshift Data Foundation 4
Timeline
- 2026-10-02 Threatist record created from CVE-2026-44664
- 2026-10-03 Alias added: GHSA-45c6-75p6-83cc
- 2026-10-27 Affected versions changed · Red Hat
References
More NaturalIntelligence vulnerabilities
- TI-2026-20935 fast-xml-parser has an entity encoding bypass via regex injection in DOCTYPE entity names CVSS 3.1CRITICAL 9.3
- TI-2026-25482 fast-xml-parser affected by numeric entity expansion bypassing all entity expansion… CVSS 3.1HIGH 7.5
- TI-2026-20291 fast-xml-parser has RangeError DoS Numeric Entities Bug CVSS 3.1HIGH 7.5
- TI-2026-32565 fast-xml-builder: Attribute values with unwanted quotes can bypass malicious or unwanted attributes CVSS 3.1MEDIUM 6.1
- TI-2026-30169 fast-xml-parser XMLBuilder: XML Comment and CDATA Injection via Unescaped Delimiters CVSS 3.1MEDIUM 6.1
- TI-2026-25755 fast-xml-parser: Entity Expansion Limits Bypassed When Set to Zero Due to JavaScript Falsy Evaluation CVSS 3.1MEDIUM 5.9
Sources
- CVE-2026-44664 · CVE Program
- CVE-2026-44664 · NVD
- FIRST EPSS
- GHSA-45c6-75p6-83cc · GitHub Advisory Database · CC BY 4.0
- CVE-2026-44664 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences