# fast-xml-parser (npm) vulnerabilities

Source: https://junglewise.ai/threats/technologies/fast-xml-parser  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Updated: 13 November 2026, 03:07 UTC. Rebuilt every hour.  
Data: https://junglewise.ai/threats/technologies/fast-xml-parser.json  
License: CC BY 4.0 with a link back

Junglewise Threat Intelligence has tracked 13 vulnerabilities in fast-xml-parser (npm): 1 in the last 7 days and 1 in the last 90 days, 1 of them critical and 0 exploited in the wild. The most recent, CVE-2026-126066, was published on 10 November 2026. Nothing was published in the last eight weeks.

## Counts

- Last 7 days: 1
- Last 30 days: 1
- Last 90 days: 1
- All time: 13 (1 critical, 0 exploited in the wild)

## About fast-xml-parser (npm)

JavaScript parser and builder for XML and JSON with validation support.

## Latest fast-xml-parser (npm) vulnerabilities

- [CVE-2026-126066: fast-xml-parser: Quadratic CPU consumption scanning unterminated stop-node tags](https://junglewise.ai/threats/cve-2026-126066-fast-xml-parser-allows-users-to-process-xml-from-js-object) (low, CVSS 3.7, published 10 Nov 2026)
- [CVE-2026-73569: fast-xml-parser DOCTYPE reset entity expansion limits bypass](https://junglewise.ai/threats/cve-2026-73569-fast-xml-parser-doctype-reset-entity-expansion-limits-bypass) (medium, CVSS 4, published 13 Aug 2026)
- [CVE-2026-41650: NaturalIntelligence fast-xml-parser XML injection in XMLBuilder](https://junglewise.ai/threats/cve-2026-41650-naturalintelligence-fast-xml-parser-xml-injection-in-xmlbuilder) (medium, CVSS 6.1, published 7 May 2026)
- [CVE-2026-33349: fast-xml-parser entity expansion bypass via falsy zero check](https://junglewise.ai/threats/cve-2026-33349-fast-xml-parser-entity-expansion-bypass-via-falsy-zero-check) (low, CVSS 3.1, published 19 Mar 2026)
- [CVE-2026-33036: fast-xml-parser numeric entity expansion bypass](https://junglewise.ai/threats/cve-2026-33036-fast-xml-parser-numeric-entity-expansion-bypass) (low, CVSS 3.1, published 17 Mar 2026)
- [CVE-2026-27942: NaturalIntelligence fast-xml-parser stack overflow in XMLBuilder](https://junglewise.ai/threats/cve-2026-27942-naturalintelligence-fast-xml-parser-stack-overflow-in-xmlbuilder) (medium, CVSS 4, published 26 Feb 2026)
- [CVE-2026-25896: NaturalIntelligence fast-xml-parser XSS via regex injection in DOCTYPE](https://junglewise.ai/threats/cve-2026-25896-naturalintelligence-fast-xml-parser-xss-via-regex-injection-in) (critical, CVSS 9.3, published 20 Feb 2026)
- [CVE-2026-26278: NaturalIntelligence fast-xml-parser denial of service via entity expansion](https://junglewise.ai/threats/cve-2026-26278-naturalintelligence-fast-xml-parser-denial-of-service-via-entity) (high, CVSS 7.5, published 19 Feb 2026)
- [CVE-2026-25128: fast-xml-parser RangeError DoS in numeric entity handling](https://junglewise.ai/threats/cve-2026-25128-naturalintelligence-fast-xml-parser-denial-of-service-via) (low, CVSS 3.1, published 30 Jan 2026)
- [CVE-2024-41818: fast-xml-parser regular expression denial of service in currency parsing](https://junglewise.ai/threats/cve-2024-41818-fast-xml-parser-regular-expression-denial-of-service-in-currency) (low, CVSS 3.1, published 29 Jul 2024)
- [fast-xml-parser regex validation method improves safety](https://junglewise.ai/threats/fast-xml-parser-regex-validation-method-improves-safety-4da37c77) (info, published 15 Jun 2023)
- [CVE-2023-34104: fast-xml-parser regex injection via DOCTYPE entities](https://junglewise.ai/threats/cve-2023-34104-fast-xml-parser-regex-injection-via-doctype-entities) (low, CVSS 3.1, published 6 Jun 2023)
- [CVE-2021-26920: Druid ingestion system Authenticated users can read data from other sources than intended](https://junglewise.ai/threats/cve-2021-26920-fast-xml-parser-prototype-pollution-via-tag-or-attribute-name) (low, CVSS 3.1, published 13 Aug 2021)

## Most severe fast-xml-parser (npm) vulnerabilities

- [CVE-2026-25896: NaturalIntelligence fast-xml-parser XSS via regex injection in DOCTYPE](https://junglewise.ai/threats/cve-2026-25896-naturalintelligence-fast-xml-parser-xss-via-regex-injection-in) (critical, CVSS 9.3, published 20 Feb 2026)
- [CVE-2026-26278: NaturalIntelligence fast-xml-parser denial of service via entity expansion](https://junglewise.ai/threats/cve-2026-26278-naturalintelligence-fast-xml-parser-denial-of-service-via-entity) (high, CVSS 7.5, published 19 Feb 2026)
- [CVE-2026-41650: NaturalIntelligence fast-xml-parser XML injection in XMLBuilder](https://junglewise.ai/threats/cve-2026-41650-naturalintelligence-fast-xml-parser-xml-injection-in-xmlbuilder) (medium, CVSS 6.1, published 7 May 2026)
- [CVE-2026-27942: NaturalIntelligence fast-xml-parser stack overflow in XMLBuilder](https://junglewise.ai/threats/cve-2026-27942-naturalintelligence-fast-xml-parser-stack-overflow-in-xmlbuilder) (medium, CVSS 4, published 26 Feb 2026)
- [CVE-2026-73569: fast-xml-parser DOCTYPE reset entity expansion limits bypass](https://junglewise.ai/threats/cve-2026-73569-fast-xml-parser-doctype-reset-entity-expansion-limits-bypass) (medium, CVSS 4, published 13 Aug 2026)
- [CVE-2026-126066: fast-xml-parser: Quadratic CPU consumption scanning unterminated stop-node tags](https://junglewise.ai/threats/cve-2026-126066-fast-xml-parser-allows-users-to-process-xml-from-js-object) (low, CVSS 3.7, published 10 Nov 2026)
- [CVE-2021-26920: Druid ingestion system Authenticated users can read data from other sources than intended](https://junglewise.ai/threats/cve-2021-26920-fast-xml-parser-prototype-pollution-via-tag-or-attribute-name) (low, CVSS 3.1, published 13 Aug 2021)
- [CVE-2023-34104: fast-xml-parser regex injection via DOCTYPE entities](https://junglewise.ai/threats/cve-2023-34104-fast-xml-parser-regex-injection-via-doctype-entities) (low, CVSS 3.1, published 6 Jun 2023)
- [CVE-2024-41818: fast-xml-parser regular expression denial of service in currency parsing](https://junglewise.ai/threats/cve-2024-41818-fast-xml-parser-regular-expression-denial-of-service-in-currency) (low, CVSS 3.1, published 29 Jul 2024)
- [CVE-2026-33036: fast-xml-parser numeric entity expansion bypass](https://junglewise.ai/threats/cve-2026-33036-fast-xml-parser-numeric-entity-expansion-bypass) (low, CVSS 3.1, published 17 Mar 2026)

## Vulnerabilities per week

Nothing was published in the last eight weeks.

| Week of | Vulns | Critical | Exploited |
| --- | --- | --- | --- |
| 17 Aug 2026 | 0 | 0 | 0 |
| 24 Aug 2026 | 0 | 0 | 0 |
| 31 Aug 2026 | 0 | 0 | 0 |
| 7 Sep 2026 | 0 | 0 | 0 |
| 14 Sep 2026 | 0 | 0 | 0 |
| 21 Sep 2026 | 0 | 0 | 0 |
| 28 Sep 2026 | 0 | 0 | 0 |
| 5 Oct 2026 | 0 | 0 | 0 |
| 12 Oct 2026 | 0 | 0 | 0 |
| 19 Oct 2026 | 0 | 0 | 0 |
| 26 Oct 2026 | 0 | 0 | 0 |
| 2 Nov 2026 | 0 | 0 | 0 |
| 9 Nov 2026 | 1 | 0 | 0 |

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- [flowise (npm)](https://junglewise.ai/threats/technologies/flowise): 133 vulnerabilities
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- [vm2 (npm)](https://junglewise.ai/threats/technologies/vm2): 111 vulnerabilities
- [electron (npm)](https://junglewise.ai/threats/technologies/electron): 77 vulnerabilities
- [ghost (npm)](https://junglewise.ai/threats/technologies/ghost): 74 vulnerabilities
- [n8n (npm)](https://junglewise.ai/threats/technologies/npm-n8n): 64 vulnerabilities
- [hono (npm)](https://junglewise.ai/threats/technologies/hono): 62 vulnerabilities
- [directus (npm)](https://junglewise.ai/threats/technologies/directus): 61 vulnerabilities
- [nocodb (npm)](https://junglewise.ai/threats/technologies/nocodb): 54 vulnerabilities
- [undici (npm)](https://junglewise.ai/threats/technologies/undici): 53 vulnerabilities
- [@budibase/server (npm)](https://junglewise.ai/threats/technologies/budibase-server): 42 vulnerabilities

## Sources

NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories. Rebuilt every hour. Cite as: Junglewise Threat Intelligence, "fast-xml-parser (npm) vulnerabilities", https://junglewise.ai/threats/technologies/fast-xml-parser, 13 November 2026.