libssh2: Integer overflow in user authenticate keyboard interactive allows out-of-bounds writes
Published Mar 25, 2019
8.8
HIGHCVSS 3.0
EPSS 3.44%
Description
A flaw was found in libssh2 before 1.8.1 creating a vulnerability on the SSH client side. A server could send a multiple keyboard interactive response messages whose total length are greater than unsigned char max characters. This value is used by the SSH client as an index to copy memory causing in an out of bounds memory write error.
Affected products
-
- Version 1.8.1StatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| The libssh2 Project | Libssh2 | n/a |
|
Configuration 2
- 8.0
Configuration 3
- n/a
Configuration 5
- 7.0
- 7.0
- 7.6
- 7.6
- 7.6
- 7.0
No data.
Red Hat Enterprise Linux 6
libssh2-0:1.4.2-3.el6_10.1
Fixed · RHSA-2019:1652
Red Hat Enterprise Linux 7
libssh2-0:1.4.3-12.el7_6.2
Fixed · RHSA-2019:0679
Red Hat Enterprise Linux 7.3 Advanced Update Support
libssh2-0:1.4.3-11.el7_3.1
Fixed · RHSA-2019:2399
Red Hat Enterprise Linux 7.3 Telco Extended Update Support
libssh2-0:1.4.3-11.el7_3.1
Fixed · RHSA-2019:2399
Red Hat Enterprise Linux 7.3 Update Services for SAP Solutions
libssh2-0:1.4.3-11.el7_3.1
Fixed · RHSA-2019:2399
Red Hat Enterprise Linux 7.4 Extended Update Support
libssh2-0:1.4.3-11.el7_4.1
Fixed · RHSA-2019:1943
Red Hat Enterprise Linux 7.5 Extended Update Support
libssh2-0:1.4.3-11.el7_5.1
Fixed · RHSA-2019:1791
Red Hat Enterprise Linux 8
virt:rhel-8000020190510171727.55190bc5
Fixed · RHSA-2019:1175
Red Hat Enterprise Linux 8 Advanced Virtualization
virt:8.0.0/libssh2
Affected
Red Hat Virtualization 4
redhat-virtualization-host
Will not fix
Red Hat Virtualization 4
rhvm-appliance
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 6 | libssh2-0:1.4.2-3.el6_10.1 | Fixed | RHSA-2019:1652 |
| Red Hat Enterprise Linux 7 | libssh2-0:1.4.3-12.el7_6.2 | Fixed | RHSA-2019:0679 |
| Red Hat Enterprise Linux 7.3 Advanced Update Support | libssh2-0:1.4.3-11.el7_3.1 | Fixed | RHSA-2019:2399 |
| Red Hat Enterprise Linux 7.3 Telco Extended Update Support | libssh2-0:1.4.3-11.el7_3.1 | Fixed | RHSA-2019:2399 |
| Red Hat Enterprise Linux 7.3 Update Services for SAP Solutions | libssh2-0:1.4.3-11.el7_3.1 | Fixed | RHSA-2019:2399 |
| Red Hat Enterprise Linux 7.4 Extended Update Support | libssh2-0:1.4.3-11.el7_4.1 | Fixed | RHSA-2019:1943 |
| Red Hat Enterprise Linux 7.5 Extended Update Support | libssh2-0:1.4.3-11.el7_5.1 | Fixed | RHSA-2019:1791 |
| Red Hat Enterprise Linux 8 | virt:rhel-8000020190510171727.55190bc5 | Fixed | RHSA-2019:1175 |
| Red Hat Enterprise Linux 8 Advanced Virtualization | virt:8.0.0/libssh2 | Affected | n/a |
| Red Hat Virtualization 4 | redhat-virtualization-host | Will not fix | n/a |
| Red Hat Virtualization 4 | rhvm-appliance | Will not fix | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This flaw was present in libssh2 packages included in Red Hat Virtualization Hypervisor and Management Appliance, however libssh2 in these hosts is never exposed to malicious clients or servers.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
1 other source (Red Hat) ▾
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
AV:N/AC:M/Au:N/C:P/I:P/A:P
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
TotalDecision
n/aAssessed Apr 23, 2025 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (24 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 3.44% (0.03437) | 88.57th | v5 (v2026.06.15) |
| Jun 15, 2026 | 3.44% (0.03437) | 87.39th | v5 (v2026.06.15) |
| Jan 25, 2026 | 8.83% (0.08827) | 92.31th | v4 (v2025.03.14) |
| Jan 20, 2026 | 7.52% (0.07518) | 91.54th | v4 (v2025.03.14) |
| Jan 8, 2026 | 8.61% (0.08613) | 92.15th | v4 (v2025.03.14) |
| Nov 21, 2025 | 9.73% (0.09733) | 92.62th | v4 (v2025.03.14) |
| Nov 18, 2025 | 2.70% (0.02704) | 84.58th | v4 (v2025.03.14) |
| Sep 22, 2025 | 10.17% (0.10165) | 92.85th | v4 (v2025.03.14) |
| Sep 17, 2025 | 8.68% (0.08682) | 92.13th | v4 (v2025.03.14) |
| Mar 30, 2025 | 9.73% (0.09733) | 92.18th | v4 (v2025.03.14) |
| Mar 29, 2025 | 24.35% (0.24354) | 93.69th | v4 (v2025.03.14) |
| Mar 17, 2025 | 9.73% (0.09733) | 92.36th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.64% (0.00636) | 79.83th | v3 (v2023.03.01) |
| Mar 18, 2024 | 0.52% (0.00522) | 76.36th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.48% (0.00481) | 75.15th | v3 (v2023.03.01) |
| Sep 3, 2023 | 0.48% (0.00481) | 72.83th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.49% (0.00488) | 72.32th | v3 (v2023.03.01) |
| Mar 6, 2023 | 2.69% (0.02686) | 82.85th | v2 (v2022.01.01) |
| Apr 1, 2022 | 2.69% (0.02686) | 81.17th | v2 (v2022.01.01) |
| Feb 4, 2022 | 18.01% (0.18006) | 93.41th | v2 (v2022.01.01) |
| Feb 3, 2022 | 13.92% (0.13924) | 89.41th | v1 |
| Jan 6, 2022 | 13.92% (0.13924) | 89.29th | v1 |
| Jan 5, 2022 | 3.48% (0.03480) | 82.48th | v5 (v2026.06.15) |
| Apr 14, 2021 | 3.48% (0.03480) | 0.00th | v1 |
References (20)
- http://lists.opensuse.org/opensuse-security-announce/2019-03/msg00040.html vendor-advisoryx_refsource_SUSEMailing ListThird Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00003.html vendor-advisoryx_refsource_SUSEThird Party Advisory
- https://access.redhat.com/errata/RHSA-2019:0679 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/errata/RHSA-2019:1175 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2019:1652 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2019:1791 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2019:1943 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2019:2399 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2019-3863 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1687313 Issue Tracking
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3863 x_refsource_CONFIRMIssue TrackingPatchThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2019/03/msg00032.html mailing-listx_refsource_MLISTMailing ListThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5DK6VO2CEUTAJFYIKWNZKEKYMYR3NO2O/ vendor-advisoryx_refsource_FEDORA
- https://nvd.nist.gov/vuln/detail/CVE-2019-3863
- https://seclists.org/bugtraq/2019/Apr/25 mailing-listx_refsource_BUGTRAQ
- https://security.netapp.com/advisory/ntap-20190327-0005/ x_refsource_CONFIRMThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2019-3863
- https://www.debian.org/security/2019/dsa-4431 vendor-advisoryx_refsource_DEBIAN
- https://www.libssh2.org/CVE-2019-3863.html x_refsource_MISCPatchVendor Advisory
- https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html x_refsource_MISC
Change history (0)
No recorded changes yet.