OESA-2026-3109

GLib is a bundle of three (formerly five) low-level system libraries written in C and developed mainly by GNOME. GLib's code was separated from GTK, so it can be used by software other than GNOME and has been developed in parallel ever since.

Security Fix(es):

A flaw was found in GLib. An integer overflow vulnerability in its Unicode case conversion implementation can lead to memory corruption. By processing specially crafted and extremely large Unicode strings, an attacker could trigger an undersized memory allocation, resulting in out-of-bounds writes. This could cause applications utilizing GLib for string conversion to crash or become unstable.(CVE-2026-1489)

A flaw was found in GLib. An off-by-one error can occur in the gvstupleis_normal function in the glib/gvariant-serialiser.c file when doing an alignment padding check because the bounds check uses > instead of >=, causing an out-of-bounds read of only 1 byte. This issue can cause a minor information disclosure of 1 byte and a denial of service when the out-of-bounds read crosses a page boundary.(CVE-2026-58010)

A flaw was found in GLib. An out-of-bounds read of only 2 bytes can occur in the gdatetimegetymd function in the glib/gdatetime.c file when an invalid GDateTime object produced by the gdatetimeaddfull function is processed. This flaw can corrupt the date output and potentially cause logic errors that may lead to a denial of service.(CVE-2026-58011)

A flaw was found in GLib. A buffer over-read can occur in the gregexreplace function when used with the G_REGEX_RAW compile flag and case-change replacement escapes because the string_append function processes matched substrings using UTF-8 functions that assume valid UTF-8 input, even when the string is treated as raw bytes. This vulnerability can cause a minor information disclosure of 1-5 bytes and a denial of service when the buffer over-read crosses a page boundary.(CVE-2026-58012)

A flaw was found in GLib. An off-by-one error can occur in the gkeyfilegetlocalestringlist function in the gkeyfile.c file when loading a key file with an empty value. This flaw can cause an out-of-bounds access of 1 byte or a denial of service when the out-of-bounds access crosses a page boundary.(CVE-2026-58014)

A flaw was found in GLib. The D-Bus client-side implementation of the DBUSCOOKIESHA1 SASL authentication mechanism does not validate the cookiecontext parameter received from the server. A malicious D-Bus server can supply a cookiecontext containing path traversal sequences, causing the client to read an arbitrary file and exfiltrate sensitive data by verifying guessed file contents against a generated hash.(CVE-2026-58015)

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.(CVE-2026-58016)