CVE-2026-58016
Description
A flaw was found in GLib. A state confusion issue exists in g_dbus_node_info_new_for_xml() in the gio/gdbusintrospection.c file when processing malformed D-Bus introspection XML, specifically with a node element nested within other elements like method, signal, property or arg. This issue can cause an unsigned integer overflow and lead to an out-of-bounds read, resulting in a denial of service.
Statement
Any applications processing D-Bus introspection XML input from untrusted sources with g_dbus_node_info_new_for_xml() are vulnerable to this issue. In GLib itself, the gdbus command line tool is the primary vector for local exploitation. However, other applications using the vulnerable function may process untrusted input in a way that allows a remote attacker to trigger this flaw. This vulnerability can cause an unsigned integer overflow and lead to an out-of-bounds read, resulting in a denial of service. As this vulnerability allows a remote attacker to cause a denial of service, it has been rated with an important severity.
Mitigation
To mitigate this vulnerability, implement input validation to sanitize untrusted D-Bus introspection XML, specifically rejecting malformed structures such as <node> elements improperly nested within <method>, <signal>, <property> or <arg> elements before calling g_dbus_node_info_new_for_xml(). Alternatively, restricting the application to only process XML input from trusted, authenticated sources will completely neutralize this issue.
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 | 7.5 | 9.1 | 7.5 |
| Attack Vector | Network | Network | Network |
| Attack Complexity | Low | Low | Low |
| Privileges Required | None | None | None |
| User Interaction | None | None | None |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | None | High | None |
| Integrity Impact | None | None | None |
| Availability Impact | High | High | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Red Hat CVSS v3 Score Explanation
The out-of-bounds read offset is not controlled by the attacker. Thus, a denial of service is the only security impact of this issue. To reflect this condition, the confidentiality metric is set to none.
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Instability
This weakness will generally lead to undefined behavior and therefore crashes. In the case of overflows involving loop index variables, the likelihood of infinite loops is also high.
Integrity
Technical Impact: Modify Memory
If the value in question is important to data (as opposed to flow), simple data corruption has occurred. Also, if the wrap around results in other conditions such as buffer overflows, further memory corruption may occur.
Confidentiality,Availability,Access Control
Technical Impact: Execute Unauthorized Code or Commands; Bypass Protection Mechanism
This weakness can sometimes trigger buffer overflows which can be used to execute arbitrary code. This is usually outside the scope of a program's implicit security policy.
Acknowledgements
Red Hat would like to thank linhlhq for reporting this issue.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
