CVE-2026-86144
Description
A flaw in libxml2's XInclude processing (xmlXIncludeProcess and xmlXIncludeProcessTree) fails to propagate parser flags like XML_PARSE_NONET. This allows custom resource loaders to fetch external network resources, potentially enabling Server-Side Request Forgery (SSRF), XML External Entity (XXE) injection, or Denial of Service (DoS) attacks.
Statement
A Moderate-severity flaw in libxml2 XInclude processing allows custom resource loaders to bypass network restriction flags, enabling unintended external network connections that could cause SSRF, information disclosure, or Denial of Service (DoS). Exploitation requires local access alongside high attack complexity, limiting its immediate widespread impact.
Mitigation
Do not expand untrusted XInclude; parse without XML_PARSE_XINCLUDE and do not call xmlXIncludeProcess / xmlXIncludeProcessTree. If XInclude is required, pass XML_PARSE_NONET (and XML_PARSE_NO_XXE where available) via xmlXIncludeProcessFlags, and restrict outbound fetches.
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 Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.6 | N/A | 5.6 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | High | N/A | High |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Changed | N/A | Changed |
| Confidentiality | Low | N/A | Low |
| Integrity Impact | Low | N/A | Low |
| Availability Impact | Low | N/A | Low |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:L
cve.org: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:L
Understanding the Weakness (CWE)
Confidentiality,Integrity
Technical Impact: Read Application Data; Modify Application Data; Unexpected State
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
