An integer overflow in the g_escape_uri_string() function of the glib library causes incorrect buffer size calculation when escaping strings with many characters needing escaping. This results in a heap-based buffer overflow, potentially allowing writes beyond the allocated memory. The vulnerability affects Red Hat Enterprise Linux versions 9 (from 9.0 up to but not including 9.8) and 10 (from 10.0 up to but not including 10.2). Red Hat has issued security advisories RHSA-2026:0936 and RHSA-2026:0975 providing updated glib2 packages that fix this issue.

The vulnerability can lead to a heap-based buffer overflow due to integer overflow in buffer size calculation, which may allow an attacker to overwrite memory. According to the CVSS v3.1 score of 7.7 (High), the impact is high on integrity and availability, but no confidentiality impact is indicated. There are no known exploits in the wild at this time.

Red Hat has released official security updates for glib2 that fix this vulnerability. Users should apply the updates provided in advisories RHSA-2026:0936 for Red Hat Enterprise Linux 9 and RHSA-2026:0975 for Red Hat Enterprise Linux 10. Detailed update instructions are available at https://access.redhat.com/articles/11258. Applying these updates mitigates the vulnerability.