CVE-2019-20840

Description

An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.60% Top 20%
Vendor Advisory fedoraproject.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory ubuntu.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/LibVNC/libvncserver/compare/LibVNCServer-0.9.12...LibVNCServer-0.9.13 third party advisory release notes
https://github.com/LibVNC/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76 third party advisory patch
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4F6FUH4EFK4NAP6GT4TQRTBKWIRCZLIY/ vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00033.html vendor advisory mailing list third party advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00055.html vendor advisory mailing list third party advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00066.html vendor advisory mailing list third party advisory
https://usn.ubuntu.com/4434-1/ third party advisory vendor advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdf third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2019-20840?
CVE-2019-20840 has been scored as a high severity vulnerability.
How to fix CVE-2019-20840?
To fix CVE-2019-20840, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-20840 being actively exploited in the wild?
It is possible that CVE-2019-20840 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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