CVE-2019-17498

In libssh2 v1.9.0 and earlier versions, the SSH_MSG_DISCONNECT logic in packet.c has an integer overflow in a bounds check, enabling an attacker to specify an arbitrary (out-of-bounds) offset for a subsequent memory read. A crafted SSH server may be able to disclose sensitive information or cause a denial of service condition on the client system when a user connects to the server.

CVSS 3.1

8.1CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H

EPSS

3.8% chance of exploitation in the next 30 days; higher than 89% of CVEs (scores of 2026-10-25)

CWE

CWE-190

Published

2019-10-21

Modified

2026-10-14

Record from

the NVD, synced 2026-10-19

Affected

• debian:debian_linux
• fedoraproject:fedora
• libssh2:libssh2
• netapp:active_iq_unified_manager
• netapp:bootstrap_os
• netapp:element_software
• netapp:hci_management_node
• netapp:ontap_select_deploy_administration_utility
• netapp:solidfire
• opensuse:leap

References

• http://lists.opensuse.org/opensuse-security-announce/2019-11/msg00026.html
• http://packetstormsecurity.com/files/172835/libssh2-1.9.0-Out-Of-Bounds-Read.html
• https://blog.semmle.com/libssh2-integer-overflow-CVE-2019-17498/
• https://github.com/kevinbackhouse/SecurityExploits/tree/8cbdbbe6363510f7d9ceec685373da12e6fc752d/libssh2/out_of_bounds_read_disconnect_CVE-2019-17498
• https://github.com/libssh2/libssh2/blob/42d37aa63129a1b2644bf6495198923534322d64/src/packet.c#L480

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