CVE-2026-103863
apache software foundation apache sling engine: no CVSS score yet. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Apache Sling Engine. Content-Type, charset, and redirect changes from an included component evade the protectheaders / checkcontenttype enforcement through setHeader(), repeated calls to setContentType(), the charset APIs, Servlet 6.1 redirect overloads, and stale config - enabling stored XSS despite enabled protections.
This issue affects Apache Sling Engine before 3.0.4.
Users are recommended to upgrade to version 3.0.4, which fixes the issue.
- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 14th percentile. Scored 2026-11-10. A forecast for this CVE across the internet, not for your own systems.
- CWEs
- CWE-79 Improper Neutralization of Input During Web Page Generation (Cross-site Scripting)
CWE-693 Protection Mechanism Failure - OWASP Top 10
- A05:2025 Injection, A06:2025 Insecure Design
- Published
- Modified
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
Ask an AI about this CVE
Show the prompt
Explain CVE-2026-103863 for an engineer deciding whether to act. Use https://cve.bz/api/public/cves/CVE-2026-103863?via=ask-ai-copy and https://cve.bz/cve/CVE-2026-103863?via=ask-ai-copy as the source of truth: what is affected and which versions fix it, whether it is in CISA KEV, public exploits, and its EPSS (an internet-wide 30-day estimate of exploitation activity, not a forecast for my systems). If they give no fixed versions, use the CVE record https://cveawg.mitre.org/api/cve/CVE-2026-103863 or the vendor advisory, not third-party mirrors. Tell me how to check whether I am affected and how to verify a fix. Cite the sources and say where they are uncertain.Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this CVE's id and public links.
Affected
- apache software foundation:apache sling engine
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| Apache Software Foundation Apache Sling Engine | before 3.0.4 |
Attack patterns (CAPEC)
- CAPEC-63 Cross-Site Scripting (XSS) Likelihood: High · Severity: Very High
- CAPEC-85 AJAX Footprinting Likelihood: High · Severity: Low
- CAPEC-209 XSS Using MIME Type Mismatch Severity: Medium
- CAPEC-588 DOM-Based XSS Likelihood: High · Severity: Very High
- CAPEC-591 Reflected XSS Likelihood: High · Severity: Very High
- CAPEC-592 Stored XSS Likelihood: High · Severity: Very High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits. More on the page of CWE-693 (17).