How severe is CVE-2019-17498?

CVE-2019-17498 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability high.

Is CVE-2019-17498 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-17498?

CVE-2019-17498 primarily affects Libssh2. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-17498?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2019-17498 published?

CVE-2019-17498 was published on 2019-10-21 and last updated on 2026-06-17.

CVE-2019-17498

CVE-2019-17498 is a high-severity vulnerability in Libssh2 with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-190.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 5.8
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-190
Affected product: Libssh2
Published: 2019-10-21
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2019-17498?: CVE-2019-17498 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability high.
Is CVE-2019-17498 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-17498?: CVE-2019-17498 primarily affects Libssh2. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-17498?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2019-17498 published?: CVE-2019-17498 was published on 2019-10-21 and last updated on 2026-06-17.

References

Affected products (12)

cpe:2.3:a:libssh2:libssh2:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:*
cpe:2.3:a:netapp:element_software:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:hci_management_node:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:bootstrap_os:-:*:*:*:*:*:*:*

More vulnerabilities in Libssh2

CVE-2019-3859 — Critical (CVSS 9.1): An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the _libssh2_packet_require and…
CVE-2019-3857 — High (CVSS 8.8): An integer overflow flaw which could lead to an out of bounds write was discovered in libssh2 before 1.8.1 in the way…
CVE-2019-3856 — High (CVSS 8.8): An integer overflow flaw, which could lead to an out of bounds write, was discovered in libssh2 before 1.8.1 in the way…
CVE-2019-3855 — High (CVSS 8.8): An integer overflow flaw which could lead to an out of bounds write was discovered in libssh2 before 1.8.1 in the way…
CVE-2026-55200 — High (CVSS 8.1): libssh2 through 1.11.1, fixed in commit 7acf3df contains an out-of-bounds write vulnerability in ssh2_transport_read()…
CVE-2019-13115 — High (CVSS 8.1): In libssh2 before 1.9.0, kex_method_diffie_hellman_group_exchange_sha256_key_exchange in kex.c has an integer overflow…

All CVEs affecting Libssh2 →

Other CWE-190 (Integer Overflow or Wraparound) vulnerabilities

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CVE-2026-24814 — Critical (CVSS 10.0): Integer Overflow or Wraparound vulnerability in swoole swoole-src (thirdparty/hiredis modules). This vulnerability is…
CVE-2025-64721 — Critical (CVSS 10.0): Sandboxie is a sandbox-based isolation software for 32-bit and 64-bit Windows NT-based operating systems. In versions…
CVE-2015-5108 — Critical (CVSS 10.0): Integer overflow in Adobe Reader and Acrobat 10.x before 10.1.15 and 11.x before 11.0.12, Acrobat and Acrobat Reader DC…
CVE-2015-5097 — Critical (CVSS 10.0): Integer overflow in Adobe Reader and Acrobat 10.x before 10.1.15 and 11.x before 11.0.12, Acrobat and Acrobat Reader DC…
CVE-2013-2555 — Critical (CVSS 10.0): Integer overflow in Adobe Flash Player before 10.3.183.75 and 11.x before 11.7.700.169 on Windows and Mac OS X, before…

Browse all CWE-190 (Integer Overflow or Wraparound) vulnerabilities →