CVE catalog
CVE-2026-33349
fast-xml-parser allows users to process XML from JS object without C/C++ based libraries or callbacks. From version 4.0.0-beta.3 to before version 5.5.7, the DocTypeReader in fast-xml-parser uses Java
- Severity
- Medium · CVSS 5.9
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.47% · Oct 25, 2026
fast-xml-parser allows users to process XML from JS object without C/C++ based libraries or callbacks. From version 4.0.0-beta.3 to before version 5.5.7, the DocTypeReader in fast-xml-parser uses JavaScript truthy checks to evaluate maxEntityCount and maxEntitySize configuration limits. When a developer explicitly sets either limit to 0 — intending to disallow all entities or restrict entity size to zero bytes — the falsy nature of 0 in JavaScript causes the guard conditions to short-circuit, completely bypassing the limits. An attacker who can supply XML input to such an application can trigger unbounded entity expansion, leading to memory exhaustion and denial of service. This issue has been patched in version 5.5.7.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | node-webfont | sid | 11.4.0+dfsg2+~cs35.7.26-22 | vulnerable |
| Debian | node-webfont | forky | 11.4.0+dfsg2+~cs35.7.26-22 | vulnerable |
| Debian | node-webfont | trixie | 11.4.0+dfsg2+~cs35.7.26-13 | vulnerable |
| Debian | node-webfont | bookworm | 11.4.0+dfsg2+~cs35.7.26-7 | vulnerable |
| Npm | fast-xml-parser | Not reported | 5.5.7 | fixed |
| Cpe | node-webfont | Not reported | Not reported | vulnerable |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | node-webfont | source | sid | (unfixed) | not yet assigned | Not reported | [1147730] |
| Debian | node-webfont | source | forky | (unfixed) | not yet assigned | Not reported | [1147730] |
| Debian | node-webfont | source | trixie | (unfixed) | not yet assigned | Not reported | [1147730] |
| Debian | node-webfont | source | bookworm | (unfixed) | not yet assigned | Not reported | [1147730] |
| Npm | fast-xml-parser | npm | Not reported | 5.5.7 | Not reported | Not reported | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [node-webfont]Affected
Details (2)
11.4.0+dfsg2+~cs35.7.26-7· all · bookwormAffected
nvd · node-webfont · debian · bookworm; nvd · node-webfont · debian · 12
11.4.0+dfsg2+~cs35.7.26-7· all · bookwormAffected
nvd · node-webfont · debian · bookworm; nvd · node-webfont · debian · 12
[Debian 13 (Trixie)]
- [node-webfont]Affected
Details (2)
11.4.0+dfsg2+~cs35.7.26-13· all · trixieAffected
nvd · node-webfont · debian · 13
11.4.0+dfsg2+~cs35.7.26-13· all · trixieAffected
nvd · node-webfont · debian · 13
Observed:
References
- [https://github.com/advisories/GHSA-jp2q-39xq-3w4g]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-33349]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-33349]
- [https://security-tracker.debian.org/tracker/CVE-2026-33349]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33349.json]
- [https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-1407.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [GitHub Advisory Database] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX]