CVE-2026-91999: CWE-79 Improper neutralization of input during web page generation ('cross-site scripting') in Apache Software Foundation Apache Sling XSS
Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Apache Sling XSS. This issue affects Apache Sling XSS: before 2.4.12. Users are recommended to upgrade to version 2.4.12, which fixes the issue.
AI Analysis
Technical Summary
This vulnerability in Apache Sling XSS involves improper neutralization of input during web page generation, classified as CWE-79 (Cross-site Scripting). It affects all versions prior to 2.4.12. The flaw allows injection of malicious scripts into web pages generated by the affected software. The Apache Software Foundation has addressed this issue in version 2.4.12.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary scripts in the context of the affected web application, potentially leading to unauthorized actions or data exposure in the user's browser session. However, no known exploits are reported in the wild at this time.
Mitigation Recommendations
Users should upgrade Apache Sling XSS to version 2.4.12 or later, where this vulnerability has been fixed. No other specific mitigations are indicated.
CVE-2026-91999: CWE-79 Improper neutralization of input during web page generation ('cross-site scripting') in Apache Software Foundation Apache Sling XSS
Description
Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Apache Sling XSS. This issue affects Apache Sling XSS: before 2.4.12. Users are recommended to upgrade to version 2.4.12, which fixes the issue.
CVSS v3.1
Score 6.1medium
Affected software
Apache Software Foundation
Apache Sling XSS
pkg:maven/org.apache.sling/org.apache.sling.xssRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in Apache Sling XSS involves improper neutralization of input during web page generation, classified as CWE-79 (Cross-site Scripting). It affects all versions prior to 2.4.12. The flaw allows injection of malicious scripts into web pages generated by the affected software. The Apache Software Foundation has addressed this issue in version 2.4.12.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary scripts in the context of the affected web application, potentially leading to unauthorized actions or data exposure in the user's browser session. However, no known exploits are reported in the wild at this time.
Mitigation Recommendations
Users should upgrade Apache Sling XSS to version 2.4.12 or later, where this vulnerability has been fixed. No other specific mitigations are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- apache
- Date Reserved
- 2026-09-15T11:11:29.968Z
- State
- PUBLISHED
Threat ID: 6ab39cddf7a7c541069439ed
Added to database: 09/23/2026, 09:33:17 UTC
Last enriched: 09/23/2026, 09:47:41 UTC
Last updated: 09/24/2026, 01:57:04 UTC
Views: 11
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