A heap‑based buffer overflow occurs when g_escape_uri_string() calculates an incorrect buffer size for strings containing many unescaped characters. The overflow can write beyond the allocated memory of the escaped string, potentially corrupting program state and causing crashes. No evidence from the description indicates that this flaw directly leads to code execution, but memory corruption may lead to unpredictable behavior.

Red Hat products that ship with glib, including Red Hat Enterprise Linux 6‑10, Ceph Storage 8, Discovery 2, and OpenShift Container Platform versions 4.12 through 4.19, are affected. Any application or service on these systems that calls g_escape_uri_string() with untrusted or large inputs could be impacted.

The CVSS score of 7.7 reflects high severity, yet the EPSS score is less than 1% and the vulnerability is not listed in CISA KEV, indicating a low probability of wild exploitation. Based on the description, it is inferred that attackers would need to supply crafted input that triggers the overflow, making the likely attack surface local or within controlled environments rather than remote code execution. No public exploitation is documented.