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TI-2023-16830 Aliases CVE-2023-33962GHSA-gwxv-jv83-6qjr

JStachio XSS vulnerability: Unescaped single quotes

Priority MEDIUM 60CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Cross-site scripting
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-79.

Summary

JStachio is a type-safe Java Mustache templating engine. Prior to version 1.0.1, JStachio fails to escape single quotes `'` in HTML, allowing an attacker to inject malicious code. This vulnerability can be exploited by an attacker to execute arbitrary JavaScript code in the context of other users visiting pages that use this template engine. This can lead to various consequences, including session hijacking, defacement of web pages, theft of sensitive information, or even the propagation of malware. Version 1.0.1 contains a patch for this issue. To mitigate this vulnerability, the template engine should properly escape special characters, including single quotes. Common practice is to escape `'` as `&#39`. As a workaround, users can avoid this issue by using only double quotes `"` for HTML attributes.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00579 47th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed jstachio (jstachio): 1.0.1io.jstach:jstachio (Maven): 1.0.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
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

VendorProductAffected versionsFixed inStatusSource
jstachiojstachiobefore 1.0.11.0.1Patch availableCNA
—io.jstach:jstachio (Maven)before 1.0.11.0.1Patch availableGHSA-gwxv-jv83-6qjr
  • jstachio Vendorjstachio Affected before 1.0.1 Fixed in 1.0.1 Patch available CNA
  • io.jstach:jstachio (Maven) Vendor— Affected before 1.0.1 Fixed in 1.0.1 Patch available GHSA-gwxv-jv83-6qjr

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:jstachio_project:jstachio:*:*:*:*:*:*:*:*before 1.0.1VulnerableJstachio Project
  • cpe:2.3:a:jstachio_project:jstachio:*:*:*:*:*:*:*:* Versions before 1.0.1 Vulnerable ·Jstachio Project

Remediation

  • Fix · CNA jstachio (jstachio) Fixed in 1.0.1
  • Fix · GHSA-gwxv-jv83-6qjr io.jstach:jstachio (Maven) Fixed in 1.0.1 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-33962
  2. 2026-10-03 Alias added: GHSA-gwxv-jv83-6qjr

References

Exploit 1

Patch 3

Advisory 1

Other 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences