CVE-2019-3861

Description

An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the way SSH packets with a padding length value greater than the packet length are parsed. A remote attacker who compromises a SSH server may be able to cause a Denial of Service or read data in the client memory.

Category

5.0
CVSS
Severity: Medium
CVSS 3.0 •
CVSS 2.0 •
EPSS 1.28% Top 25%
Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory fedoraproject.org Vendor Advisory debian.org Vendor Advisory redhat.com Vendor Advisory libssh2.org
Affected: The libssh2 Project libssh2
Published at:
Updated at:

References

Link Tags
https://www.libssh2.org/CVE-2019-3861.html patch vendor advisory
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3861 issue tracking third party advisory patch
https://lists.debian.org/debian-lts-announce/2019/03/msg00032.html third party advisory mailing list
https://security.netapp.com/advisory/ntap-20190327-0005/ third party advisory
http://lists.opensuse.org/opensuse-security-announce/2019-03/msg00040.html mailing list third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00003.html third party advisory vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5DK6VO2CEUTAJFYIKWNZKEKYMYR3NO2O/ vendor advisory
https://www.debian.org/security/2019/dsa-4431 vendor advisory
https://seclists.org/bugtraq/2019/Apr/25 mailing list
https://access.redhat.com/errata/RHSA-2019:2136 vendor advisory
https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html

Frequently Asked Questions

What is the severity of CVE-2019-3861?
CVE-2019-3861 has been scored as a medium severity vulnerability.
How to fix CVE-2019-3861?
To fix CVE-2019-3861, 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-2019-3861 being actively exploited in the wild?
It is possible that CVE-2019-3861 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2019-3861?
CVE-2019-3861 affects The libssh2 Project libssh2.
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