Updated: 2025-08-20 00:08:14.330991
Description:
A heap-based buffer over-read vulnerability was found in the X.org server's ProcXIGetSelectedEvents() function. This issue occurs when byte-swapped length values are used in replies, potentially leading to memory leakage and segmentation faults, particularly when triggered by a client with a different endianness. This vulnerability could be exploited by an attacker to cause the X server to read heap memory values and then transmit them back to the client until encountering an unmapped page, resulting in a crash. Despite the attacker's inability to control the specific memory copied into the replies, the small length values typically stored in a 32-bit integer can result in significant attempted out-of-bounds reads.
| Links | NIST | CIRCL | RHEL | Ubuntu |
| Severity | Score | |
|---|---|---|
| CVSS Version 2.x | NONE | 0.0 |
| CVSS Version 3.x | HIGH | 7.3 |
| OS name | Project name | Version | Score | Severity | Status | Errata | Last updated | Statement |
|---|---|---|---|---|---|---|---|---|
| AlmaLinux 9.2 ESU | xorg-x11-server-Xwayland | 21.1.3 | 7.3 | HIGH | Released | CLSA-2025:1763651916 | 2025-11-20 21:01:42 | |
| AlmaLinux 9.2 ESU | tigervnc | 1.12.0 | 7.3 | HIGH | Released | CLSA-2025:1744223313 | 2025-04-10 03:12:19 |