CVE-2026-52720: Gstreamer1-plugins-bad-free: gstreamer: heap buffer overflow via crafted vnc server rectangle in librfb

Vulnerability summary

CVE-2026-52720 is a high (CVSS 8.8) Heap-based Buffer Overflow vulnerability in gst-plugins-bad1.0. EPSS estimates a 0.64% chance of exploitation in the next 30 days, higher than 49.9% of scored vulnerabilities.

Timeline

1. 15-06-2026
   PublishedVulnerability first disclosed.
2. 03-08-2026
   Last modifiedVulnerability information updated.

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.

• CWE-122Heap-based Buffer OverflowA heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().