CVE-2019-3859

Severity: critical (CVSS 9.1 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 6.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-03-21 · updated 2026-10-14
Weakness: CWE-125

Description

An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the _libssh2_packet_require and _libssh2_packet_requirev functions. A remote attacker who compromises a SSH server may be able to cause a Denial of Service or read data in the client memory.

Affected products

Debian Linux: 8.0, 9.0
Fedoraproject Fedora: 28, 29
libssh2: before 1.8.1 — fixed in 1.8.1
NetApp ONTAP Select Deploy administration utility: all versions
openSUSE Leap: 15.0, 42.3

How to fix

Upgrade to a fixed version: libssh2 1.8.1. Check the vendor advisory for mitigations.

References

http://lists.opensuse.org/opensuse-security-announce/2019-03/msg00040.html
http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00003.html
http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00102.html
http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00103.html
http://packetstormsecurity.com/files/152136/Slackware-Security-Advisory-libssh2-Updates.html
http://www.openwall.com/lists/oss-security/2019/03/18/3
http://www.securityfocus.com/bid/107485
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3859
https://lists.debian.org/debian-lts-announce/2019/03/msg00032.html
https://lists.debian.org/debian-lts-announce/2019/04/msg00006.html
https://lists.debian.org/debian-lts-announce/2019/07/msg00024.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5DK6VO2CEUTAJFYIKWNZKEKYMYR3NO2O/

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