CVE-2026-58016: Glib: integer underflow in gio/gdbusintrospection.c via "g_dbus_node_info_new_for_xml"
A flaw was found in GLib. A state confusion issue exists in gdbusnodeinfonewforxml() 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.
Other sources
A state confusion vulnerability exists in gdbusnodeinfonewforxml() in gio/gdbusintrospection.c. When parsing malformed D-Bus introspection XML containing a <node> element nested inside <method>, <signal>, <property>, or <arg> elements, the parser's internal state becomes inconsistent. The nested </interface> closing tag inside the nested <node> steals and resets the shared data->methods (or data->signals/data->properties) array to an empty state. When the outer </method> (or similar) closing tag subsequently calls parsedatagetmethod(data, FALSE), it accesses pdata[len - 1] with len == 0, causing an unsigned integer underflow (0u - 1 = 0xFFFFFFFF) and a massive out-of-bounds heap read at offset 0xFFFFFFFF sizeof(gpointer) (~8 GB before the buffer).
— Red Hat
Glib: integer underflow in gio/gdbusintrospection.c via "gdbusnodeinfonewforxml"
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 2.78.6-10
Event History
Frequently Asked Questions
What is the severity of CVE-2026-58016?
CVE-2026-58016 has a critical severity rating of 9.1.
How do I fix CVE-2026-58016?
To address CVE-2026-58016, users should update GLib to the latest version provided by Red Hat or the relevant vendor.
What type of vulnerability is CVE-2026-58016?
CVE-2026-58016 is categorized as an integer underflow vulnerability.
Which software is affected by CVE-2026-58016?
CVE-2026-58016 affects GLib and is relevant to systems running Red Hat Enterprise Linux.
Is CVE-2026-58016 remotely exploitable?
Yes, CVE-2026-58016 is remotely exploitable, as it involves a state confusion issue when processing malformed D-Bus introspection XML.