RHSA-2026:55440 - Security Advisory

Topic

An update for glib2 is now available for Red Hat Enterprise Linux 9.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

GLib provides the core application building blocks for libraries and applications written in C. It provides the core object system used in GNOME, the main loop implementation, and a large set of utility functions for strings and common data structures.

Security Fix(es):

• glib: buffer over-read in glib/gvariant-serialiser.c via gvs_tuple_is_normal() (CVE-2026-58010)
• glib: out-of-bounds read in glib/gdatetime.c:g_date_time_get_ymd via invalid GDateTime (CVE-2026-58011)
• glib: buffer over-read in g_regex_replace() via glib/gregex.c:string_append() and g_utf8_next_char() (CVE-2026-58012)
• glib: buffer over-read in glib/giochannel.c via "g_io_channel_read_line_backend" (CVE-2026-58013)
• glib: off-by-one error in glib/gkeyfile.c via "g_key_file_get_locale_string_list" (CVE-2026-58014)
• glib: path traversal in glib/gio/gdbusauthmechanismsha1.c via keyring_lookup_entry and mechanism_client_data_receive (CVE-2026-58015)
• GDBusServer: glib2: GDBusServer pre-authentication DoS via unbounded SASL line buffering (CVE-2026-15588)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 9 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 9.8 x86_64
• Red Hat Enterprise Linux for IBM z Systems 9 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 9.8 s390x
• Red Hat Enterprise Linux for Power, little endian 9 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 9.8 ppc64le
• Red Hat Enterprise Linux for ARM 64 9 aarch64
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 9.8 aarch64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 9.8 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 9.8 x86_64
• Red Hat CodeReady Linux Builder for x86_64 9 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian 9 ppc64le
• Red Hat CodeReady Linux Builder for ARM 64 9 aarch64
• Red Hat CodeReady Linux Builder for IBM z Systems 9 s390x
• Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 9.8 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 9.8 ppc64le
• Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support 9.8 s390x
• Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 9.8 aarch64
• Red Hat Enterprise Linux for ARM 64 - 4 years of updates 9.8 aarch64
• Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 9.8 s390x
• Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 9.8 x86_64
• Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 9.8 aarch64
• Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 9.8 ppc64le
• Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 9.8 s390x

Fixes

• BZ - 2492243 - CVE-2026-58010 glib: buffer over-read in glib/gvariant-serialiser.c via gvs_tuple_is_normal()
• BZ - 2492245 - CVE-2026-58011 glib: out-of-bounds read in glib/gdatetime.c:g_date_time_get_ymd via invalid GDateTime
• BZ - 2492247 - CVE-2026-58012 glib: buffer over-read in g_regex_replace() via glib/gregex.c:string_append() and g_utf8_next_char()
• BZ - 2492248 - CVE-2026-58013 glib: buffer over-read in glib/giochannel.c via "g_io_channel_read_line_backend"
• BZ - 2492255 - CVE-2026-58014 glib: off-by-one error in glib/gkeyfile.c via "g_key_file_get_locale_string_list"
• BZ - 2492256 - CVE-2026-58015 glib: path traversal in glib/gio/gdbusauthmechanismsha1.c via keyring_lookup_entry and mechanism_client_data_receive
• BZ - 2499675 - CVE-2026-15588 GDBusServer: glib2: GDBusServer pre-authentication DoS via unbounded SASL line buffering

CVEs

• CVE-2026-15588
• CVE-2026-58010
• CVE-2026-58011
• CVE-2026-58012
• CVE-2026-58013
• CVE-2026-58014
• CVE-2026-58015

References

• https://access.redhat.com/security/updates/classification/#moderate