CVE-2026-39826

Description

A flaw was found in html/template. A trusted template author could craft a script tag with an empty or whitespace-only 'type' attribute. This vulnerability causes the template engine to incorrectly escape data passed into the script block, potentially leading to cross-site scripting (XSS). An attacker could leverage this to execute arbitrary client-side scripts in a user's browser.

Mitigation

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.4N/A6.1
Attack VectorNetworkN/ANetwork
Attack ComplexityLowN/ALow
Privileges RequiredNoneN/ANone
User InteractionRequiredN/ARequired
ScopeUnchangedN/AChanged
ConfidentialityLowN/ALow
Integrity ImpactLowN/ALow
Availability ImpactNoneN/ANone

Vector

Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Understanding the Weakness (CWE)

Other

Technical Impact: Varies by Context

Frequently Asked Questions

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