CVE-2026-50538

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.40% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 34.3% of scored records. A rank, not a probability.

NVD base score

8.8 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

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

NVD analysis status

Deferred. NVD last modified this record on 2026-10-12.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-08-21 21:03Z2 MO AGO

Last updated

2026-08-24 19:39Z2 MO AGO

Reserved

2026-06-04

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

High (CVSS 8.8)

CNA CVSS vector

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

Weaknesses

• CWE-122Heap-based Buffer OverflowVariant
• CWE-787Out-of-bounds WriteBase

Data version

5.2

Document digest

815a4c0341a751f021fc15387d06a86802f203948b9240b009a2cf8d4e6762c9

• github.comhttps://github.com/LibVNC/libvncserver/security/advisories/GHSA-v9pm-47h4-jcq8x_refsource_CONFIRM
• github.comhttps://github.com/LibVNC/libvncserver/commit/540332be3e0acc566fa64da6f1b4680c72c724ddx_refsource_MISC