CVE-2018-20021
Status: ModifiedHigh (7.5)—
LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM
CVSS
- Version: 3.0
- Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Base score: 7.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 3.52%
- Percentile among all scored CVEs: 89
- Score date: 10/5/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (3)
CWEs
- CWE-835
References
- https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-031-libvnc-infinite-loop/
- https://lists.debian.org/debian-lts-announce/2018/12/msg00017.html
- https://lists.debian.org/debian-lts-announce/2019/10/msg00042.html
- https://lists.debian.org/debian-lts-announce/2019/11/msg00033.html
- https://lists.debian.org/debian-lts-announce/2019/12/msg00028.html
- https://security.gentoo.org/glsa/201908-05
- https://security.gentoo.org/glsa/202006-06
- https://usn.ubuntu.com/3877-1/
- https://usn.ubuntu.com/4547-1/
- https://usn.ubuntu.com/4547-2/
- https://usn.ubuntu.com/4587-1/
- https://www.debian.org/security/2019/dsa-4383
- https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-031-libvnc-infinite-loop/
- https://lists.debian.org/debian-lts-announce/2018/12/msg00017.html
- https://lists.debian.org/debian-lts-announce/2019/10/msg00042.html
- https://lists.debian.org/debian-lts-announce/2019/11/msg00033.html
- https://lists.debian.org/debian-lts-announce/2019/12/msg00028.html
- https://security.gentoo.org/glsa/201908-05
- https://security.gentoo.org/glsa/202006-06
- https://usn.ubuntu.com/3877-1/
- https://usn.ubuntu.com/4547-1/
- https://usn.ubuntu.com/4547-2/
- https://usn.ubuntu.com/4587-1/
- https://www.debian.org/security/2019/dsa-4383
Raw JSON (NVD)
Show
{
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"cveTags": [],
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},
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}
],
"lastModified": "2026-06-17T01:52:11.067",
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