Vulnary
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Critical· 9.3official fix available

CVE-2026-25896

The fast‑xml‑parser library can be tricked into replacing standard XML entities with attacker‑controlled values, allowing malicious scripts to be injected into parsed XML. This flaw exists in versions 4.1.3 through 5.3.4 and can be exploited when the parsed output is rendered in a web application.

publishedFeb 20, 2026
last modifiedJul 21, 2026
sourcesNVD
severity · cvss
9.3
critical · how bad it is
exploitation · epss
<1%
38th percentile · chance of exploitation in 30 days
(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →
auto-deletes from the system
counting…on Aug 19, 2026

An official fix is available, so this entry is kept for 30 days and then removed automatically.

01

Who is affected

The naturalintelligence fast‑xml‑parser library, versions 4.1.3 to 5.3.4, used in Node.js applications.

02

Real-world impact

An attacker could embed malicious JavaScript into XML data that, when parsed and displayed by a web application, would run in the victim’s browser, enabling cross‑site scripting attacks.

03

Why this severity

The CVSS score of 9.3 reflects that the vulnerability is network‑exploitable with no authentication or user interaction, and it can compromise the confidentiality of the attacker’s data (high impact).

04

What to do about it

official fix available
recommended steps
  1. 01Upgrade fast-xml-parser to version 5.3.5 or later.

NVD-referenced vendor advisory

05

Timeline

  1. Feb 20, 2026 · Feb 20, 2026
    Published
    Disclosed and added to the National Vulnerability Database.
  2. Jul 20, 2026 · 16d ago
    Official fix available
    A vendor patch or mitigation now exists — see the remediation steps above.
  3. Jul 21, 2026 · 15d ago
    Advisory updated
    The NVD record was last revised.
06

How it’s attacked

Attack vectorNetwork (remote)
Attack complexityLow
Privileges requiredNone
User interactionNone needed
ScopeChanged
Confidentiality impactLow
Integrity impactHigh
Availability impactNone
07

References & advisories

NVD advisory ↗Search advisories ↗
(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →