Description
A heap buffer overflow vulnerability was found in GStreamer's librfb (RFB/VNC client). The rectangle bounds check incorrectly validates area rather than individual dimensions, allowing a malicious VNC server to send a rectangle that extends beyond the framebuffer. A remote attacker could set up a malicious VNC server and trick a user into connecting, resulting in an out-of-bounds heap write that could lead to code execution or a crash.
Problem types
Product status
Timeline
| 2026-05-19: | Reported to Red Hat. |
| 2026-06-15: | Made public. |
Credits
Red Hat would like to thank JUNYI LIU for reporting this issue.
References
access.redhat.com/security/cve/CVE-2026-52720
bugzilla.redhat.com/show_bug.cgi?id=2486731 (RHBZ#2486731)
gitlab.freedesktop.org/gstreamer/gstreamer/-/work_items/5105