CVE-2026-109833: Stack Overflow (CVSS 5.9)

Description

A flaw was found in gnome-remote-desktop as shipped in Red Hat Enterprise Linux. In the VNC TLS read path, partial consumption of the internal peek buffer incorrectly moves remaining peeked bytes into the caller-supplied buffer instead of compacting the peek buffer. A remote attacker who can reach an enabled VNC TLS listener and trigger a peek/read size mismatch can cause an out-of-bounds write, leading to denial of service.

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CVSS v3.1 Score

5.9

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0037

Probability of exploitation

0.29%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-121 CWE-121

References

Other References

https://access.redhat.com/security/cve/CVE-2026-109833 https://bugzilla.redhat.com/show_bug.cgi?id=2550367

Frequently Asked Questions

What is CVE-2026-109833? +

A flaw was found in gnome-remote-desktop as shipped in Red Hat Enterprise Linux. In the VNC TLS read path, partial consumption of the internal peek buffer incorrectly moves remaining peeked bytes into the caller-supplied buffer instead of compacting the peek buffer. A remote attacker who can reach an enabled VNC TLS listener and trigger a peek/read size mismatch can cause an out-of-bounds write, leading to denial of service. It has a CVSS v3.1 base score of 5.9 (MEDIUM).

How severe is CVE-2026-109833? +

CVE-2026-109833 has a CVSS v3.1 score of 5.9 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0037, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-109833? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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