CVE-2018-20748

Exploitation

Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.

SSVC decision

Not assessed by CISA

EPSS probability

3.26% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 87.3% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

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

2019-01-30 18:00Z7 YR AGO

Last updated

2024-08-05 12:12Z2 YR AGO

Reserved

2019-01-30

Assigning CNA

mitre

Record state

PUBLISHED

Severity

Not rated by the issuing CNA

CNA CVSS vector

Not published by the issuing CNA

Weaknesses

• CWE-787Out-of-bounds WriteBase
• CWE-416Use After FreeVariant

Data version

5.1

Document digest

eaf4b638f1541d307f5400e1ac88837645589b4540b0f3d2f483660c48c2352a

• lists.debian.org[debian-lts-announce] 20190131 [SECURITY] [DLA 1652-1] libvncserver security updatehttps://lists.debian.org/debian-lts-announce/2019/01/msg00029.htmlmailing-listx_refsource_MLIST
• github.comhttps://github.com/LibVNC/libvncserver/commit/a64c3b37af9a6c8f8009d7516874b8d266b42baex_refsource_MISC
• github.comhttps://github.com/LibVNC/libvncserver/commit/e34bcbb759ca5bef85809967a268fdf214c1ad2cx_refsource_MISC
• github.comhttps://github.com/LibVNC/libvncserver/issues/273x_refsource_MISC
• github.comhttps://github.com/LibVNC/libvncserver/commit/c5ba3fee85a7ecbbca1df5ffd46d32b92757bc2ax_refsource_MISC
• github.comhttps://github.com/LibVNC/libvncserver/commit/c2c4b81e6cb3b485fb1ec7ba9e7defeb889f6ba7x_refsource_MISC
• usn.ubuntu.comUSN-3877-1https://usn.ubuntu.com/3877-1/vendor-advisoryx_refsource_UBUNTU
• www.openwall.comhttps://www.openwall.com/lists/oss-security/2018/12/10/8x_refsource_MISC
• lists.debian.org[debian-lts-announce] 20191030 [SECURITY] [DLA 1979-1] italc security updatehttps://lists.debian.org/debian-lts-announce/2019/10/msg00042.htmlmailing-listx_refsource_MLIST
• usn.ubuntu.comUSN-4547-1https://usn.ubuntu.com/4547-1/vendor-advisoryx_refsource_UBUNTU
• usn.ubuntu.comUSN-4587-1https://usn.ubuntu.com/4587-1/vendor-advisoryx_refsource_UBUNTU
• cert-portal.siemens.comhttps://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdfx_refsource_CONFIRM