A buffer overflow exists in libX11's processing of XkbGetMap requests. The overflow occurs when the key_sym_map buffer is written beyond its bounds, allowing an attacker to possibly execute arbitrary code within the context of a program that depends on libX11. The flaw exists in library versions prior to 1.8.14 and can be triggered by a malicious X server that sends specially crafted data.

The vulnerability affects the X.Org libX11 library from the x.org project. All versions older than 1.8.14 are susceptible. The issue was identified in the release prior to 1.8.14.

The CVSS score of 7.5 indicates a high potential impact, while the EPSS score of < 1% indicates a low exploitation probability. The flaw is not yet listed in the CISA KEV catalog, which further reduces the likelihood of widespread exploitation. However, a malicious X server can be run locally or over a network to deliver the attack. Therefore, the risk remains moderate to high, especially on systems that allow external X server connections.