CVE-2025-4373: Glib: buffer underflow on glib through glib/gstring.c via function g_string_insert_unichar

Severity: medium (CVSS 4.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-05-06 · updated 2026-09-21
Weakness: CWE-124

Description

A flaw was found in GLib, which is vulnerable to an integer overflow in the g_string_insert_unichar() function. When the position at which to insert the character is large, the position will overflow, leading to a buffer underwrite.

Affected products

Red Hat Enterprise Linux 10: all versions — fixed in 0:2.80.4-4.el10_0.6
Red Hat Enterprise Linux 6: all versions
Red Hat Enterprise Linux 7: all versions
Red Hat Enterprise Linux 8: all versions — fixed in 0:2.56.4-166.el8_10
Red Hat Enterprise Linux 8.2 Advanced Update Support: all versions — fixed in 0:2.56.4-8.el8_2.2
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support: all versions — fixed in 0:2.56.4-10.el8_4.2
Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On: all versions — fixed in 0:2.56.4-10.el8_4.2
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support: all versions — fixed in 0:2.56.4-158.el8_6.2
Red Hat Enterprise Linux 8.6 Telecommunications Update Service: all versions — fixed in 0:2.56.4-158.el8_6.2
Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions: all versions — fixed in 0:2.56.4-158.el8_6.2
Red Hat Enterprise Linux 8.8 Telecommunications Update Service: all versions — fixed in 0:2.56.4-162.el8_8
Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions: all versions — fixed in 0:2.56.4-162.el8_8
Red Hat Enterprise Linux 9: all versions — fixed in 0:2.68.4-16.el9_6.2
Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions: all versions — fixed in 0:2.68.4-5.el9_0.2
Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions: all versions — fixed in 0:2.68.4-7.el9_2.2
Red Hat Enterprise Linux 9.4 Extended Update Support: all versions — fixed in 0:2.68.4-14.el9_4.3
Red Hat Insights proxy 1.5: all versions — fixed in 1.5.5-1754504343
Red Hat OpenShift distributed tracing 3.6.0: all versions — fixed in rhosdt-3.6-1753265314, rhosdt-3.6-1753265330, rhosdt-3.6-1753265332, rhosdt-3.6-1753265342, rhosdt-3.6-1753265394, rhosdt-3.6-1753265411

How to fix

Upgrade to a fixed version: Red Hat Enterprise Linux 10 0:2.80.4-4.el10_0.6; Red Hat Enterprise Linux 8 0:2.56.4-166.el8_10; Red Hat Enterprise Linux 8.2 Advanced Update Support 0:2.56.4-8.el8_2.2; Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support 0:2.56.4-10.el8_4.2; Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On 0:2.56.4-10.el8_4.2; Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support 0:2.56.4-158.el8_6.2; Red Hat Enterprise Linux 8.6 Telecommunications Update Service 0:2.56.4-158.el8_6.2; Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions 0:2.56.4-158.el8_6.2; Red Hat Enterprise Linux 8.8 Telecommunications Update Service 0:2.56.4-162.el8_8; Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions 0:2.56.4-162.el8_8; Red Hat Enterprise Linux 9 0:2.68.4-16.el9_6.2; Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions 0:2.68.4-5.el9_0.2. Check the vendor advisory for mitigations.

References

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