CVE-2026-52720
A heap buffer overflow vulnerability was found in GStreamer's librfb (RFB/VNC client).
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.64%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- EPSS
- 0.64% probability · 49th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-122
- Source
- secalert@redhat.com
References
- https://access.redhat.com/errata/RHSA-2026:36749
- https://access.redhat.com/errata/RHSA-2026:36834
- https://access.redhat.com/errata/RHSA-2026:37130
- https://access.redhat.com/errata/RHSA-2026:47069
- https://access.redhat.com/errata/RHSA-2026:47070
- https://access.redhat.com/errata/RHSA-2026:47071
- https://access.redhat.com/errata/RHSA-2026:47075
- https://access.redhat.com/errata/RHSA-2026:47076
- https://access.redhat.com/errata/RHSA-2026:47176
- https://access.redhat.com/errata/RHSA-2026:47717
- https://access.redhat.com/errata/RHSA-2026:47718
- https://access.redhat.com/errata/RHSA-2026:49517
- https://access.redhat.com/security/cve/CVE-2026-52720
- https://bugzilla.redhat.com/show_bug.cgi?id=2486731
- https://gitlab.freedesktop.org/gstreamer/gstreamer/-/work_items/5105
- https://access.redhat.com/errata/RHSA-2026:36749
- https://access.redhat.com/errata/RHSA-2026:36834
- https://access.redhat.com/errata/RHSA-2026:37130
- https://access.redhat.com/errata/RHSA-2026:47069
- https://access.redhat.com/errata/RHSA-2026:47070
- https://access.redhat.com/errata/RHSA-2026:47071
- https://access.redhat.com/errata/RHSA-2026:47075
- https://access.redhat.com/errata/RHSA-2026:47076
- https://access.redhat.com/errata/RHSA-2026:47176
- https://access.redhat.com/errata/RHSA-2026:47717
- https://access.redhat.com/errata/RHSA-2026:47718
- https://access.redhat.com/errata/RHSA-2026:49517
- https://access.redhat.com/security/cve/CVE-2026-52720
- https://bugzilla.redhat.com/show_bug.cgi?id=2486731
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52720.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.