Application crash via unbounded schema include recursion
Published Jan 15, 2026 · Updated Jan 15, 2026
Uncontrolled recursion in the libxml2 RelaxNG parser allows remote attackers to crash applications through crafted schema inclusions. The external-schema include handler follows nested directives without tracking or enforcing an inclusion-depth limit, recursively consuming the call stack. Exploitation requires an application to parse an attacker-controlled RelaxNG schema; successful input exhausts the stack and terminates that process without reported data disclosure or modification.
Summary
What happened
Uncontrolled recursion in the libxml2 RelaxNG parser allows remote attackers to crash applications through crafted schema inclusions. The external-schema include handler follows nested directives without tracking or enforcing an inclusion-depth limit, recursively consuming the call stack. Exploitation requires an application to parse an attacker-controlled RelaxNG schema; successful input exhausts the stack and terminates that process without reported data disclosure or modification.
The record
- CVE
- CVE-2026-0989
- Published
- Jan 15, 2026
- Updated
- Jan 15, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat JBoss Core Services
- Classifications
- CWE-674, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 15, 2026CVE publishedPublication date reported by the CVE source.
- Jan 15, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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