CVE-2026-59691 Gstreamer1-plugins-bad-free: gstreamer: rfbsrc/librfb hextile heap out-of-bounds write with 16bpp framebuffer
A heap buffer overflow in GStreamer's rfbsrc plugin allows remote attackers to cause denial of service or potential code execution via malicious VNC server responses.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-59691?
CVE-2026-59691 is a high-severity memory corruption vulnerability in Red Hat Enterprise Linux 10, published on 9 Jul 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
A heap buffer overflow vulnerability was found in GStreamer's rfbsrc plugin. When a client connects to a malicious RFB/VNC server that advertises a 16bpp framebuffer and sends Hextile-encoded updates, the Hextile background fill path writes 32-bit pixel values into a buffer allocated for 16-bit pixels. This type mismatch causes an out-of-bounds heap write that can lead to denial of service (process crash) and potential memory corruption.
Weakness: CWE-787
Which versions are affected by CVE-2026-59691?
Linux distribution packages (4)
gstreamer-plugins-bad-free Red Hat:rhel_els:7 | All versions | 0:0.10.23-26.el7_9 |
gstreamer-plugins-bad-free-debuginfo Red Hat:rhel_els:7 | All versions | 0:0.10.23-26.el7_9 |
gstreamer-plugins-bad-free-devel Red Hat:rhel_els:7 | All versions | 0:0.10.23-26.el7_9 |
gstreamer-plugins-bad-free-devel-docs Red Hat:rhel_els:7 | All versions | 0:0.10.23-26.el7_9 |
How do I fix CVE-2026-59691?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-59691 being exploited?
There is no known exploitation of CVE-2026-59691 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-59691, ECHO-ae12-ba77-0223, GHSA-g4ff-54hw-hj6r, RHSA-2026:62532, UBUNTU-CVE-2026-59691.