libssh2: Out-of-bounds memory comparison with specially crafted message channel request
Published Mar 20, 2019
9.1
CRITICALCVSS 3.0
EPSS 7.90%
Description
An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the way SSH_MSG_CHANNEL_REQUEST packets with an exit status message and no payload 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.
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
- 29
Configuration 3
- 8.0
Configuration 4
- n/a
No data.
Red Hat Ansible Tower 3.4 for RHEL 7
ansible-tower-34/ansible-tower-memcached:1.4.15-28
Fixed · RHBA-2020:0547
Red Hat Ansible Tower 3.4 for RHEL 7
ansible-tower-35/ansible-tower-memcached:1.4.15-28
Fixed · RHBA-2020:0547
Red Hat Ansible Tower 3.4 for RHEL 7
ansible-tower-37/ansible-tower-memcached-rhel7:1.4.15-28
Fixed · RHBA-2020:0547
Red Hat Enterprise Linux 7
libssh2-0:1.4.3-12.el7_6.3
Fixed · RHSA-2019:1884
Red Hat Enterprise Linux 6
libssh2
Will not fix
Red Hat Enterprise Linux 8
virt:rhel/libssh2
Not affected
Red Hat Enterprise Linux 8 Advanced Virtualization
virt:8.0.0/libssh2
Will not fix
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 Ansible Tower 3.4 for RHEL 7 | ansible-tower-34/ansible-tower-memcached:1.4.15-28 | Fixed | RHBA-2020:0547 |
| Red Hat Ansible Tower 3.4 for RHEL 7 | ansible-tower-35/ansible-tower-memcached:1.4.15-28 | Fixed | RHBA-2020:0547 |
| Red Hat Ansible Tower 3.4 for RHEL 7 | ansible-tower-37/ansible-tower-memcached-rhel7:1.4.15-28 | Fixed | RHBA-2020:0547 |
| Red Hat Enterprise Linux 7 | libssh2-0:1.4.3-12.el7_6.3 | Fixed | RHSA-2019:1884 |
| Red Hat Enterprise Linux 6 | libssh2 | Will not fix | n/a |
| Red Hat Enterprise Linux 8 | virt:rhel/libssh2 | Not affected | n/a |
| Red Hat Enterprise Linux 8 Advanced Virtualization | virt:8.0.0/libssh2 | Will not fix | 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. libssh2 is no longer included in the virt module since Red Hat Enterprise Linux 8.1.
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:N/S:U/C:H/I:N/A:H
1 other source (Red Hat) ▾
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
AV:N/AC:L/Au:N/C:P/I:N/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 3, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (19 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 7.90% (0.07898) | 94.55th | v5 (v2026.06.15) |
| Jun 15, 2026 | 8.11% (0.08114) | 94.08th | v5 (v2026.06.15) |
| Aug 28, 2025 | 5.88% (0.05880) | 90.23th | v4 (v2025.03.14) |
| Aug 23, 2025 | 4.35% (0.04352) | 88.48th | v4 (v2025.03.14) |
| Aug 21, 2025 | 7.39% (0.07386) | 91.33th | v4 (v2025.03.14) |
| Mar 30, 2025 | 5.73% (0.05732) | 89.51th | v4 (v2025.03.14) |
| Mar 29, 2025 | 19.44% (0.19440) | 92.46th | v4 (v2025.03.14) |
| Mar 17, 2025 | 5.73% (0.05732) | 89.76th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.91% (0.00908) | 83.47th | v3 (v2023.03.01) |
| Mar 13, 2024 | 1.45% (0.01450) | 86.33th | v3 (v2023.03.01) |
| Jul 14, 2023 | 0.99% (0.00988) | 81.47th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.70% (0.00698) | 77.19th | v3 (v2023.03.01) |
| Mar 6, 2023 | 3.78% (0.03779) | 85.48th | v2 (v2022.01.01) |
| Apr 1, 2022 | 3.78% (0.03779) | 84.01th | v2 (v2022.01.01) |
| Feb 4, 2022 | 37.15% (0.37149) | 97.07th | v2 (v2022.01.01) |
| Feb 3, 2022 | 22.12% (0.22115) | 94.76th | v1 |
| Jan 6, 2022 | 22.12% (0.22115) | 94.70th | v1 |
| Sep 1, 2021 | 5.95% (0.05952) | 89.51th | v1 |
| Apr 14, 2021 | 5.95% (0.05952) | 0.00th | v1 |
References (22)
- 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
- http://packetstormsecurity.com/files/152136/Slackware-Security-Advisory-libssh2-Updates.html x_refsource_MISCPatchThird Party AdvisoryVDB Entry
- http://www.openwall.com/lists/oss-security/2019/03/18/3 mailing-listx_refsource_MLISTMailing ListPatchThird Party Advisory
- http://www.securityfocus.com/bid/107485 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/errata/RHSA-2019:1884 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2019-3862 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1687312 Issue Tracking
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3862 x_refsource_CONFIRMIssue Tracking
- 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://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XCWEA5ZCLKRDUK62QVVYMFWLWKOPX3LO/ vendor-advisoryx_refsource_FEDORA
- https://nvd.nist.gov/vuln/detail/CVE-2019-3862
- https://seclists.org/bugtraq/2019/Apr/25 mailing-listx_refsource_BUGTRAQ
- https://seclists.org/bugtraq/2019/Mar/25 mailing-listx_refsource_BUGTRAQMailing ListPatchThird Party Advisory
- https://security.netapp.com/advisory/ntap-20190327-0005/ x_refsource_CONFIRMThird Party Advisory
- https://www.broadcom.com/support/fibre-channel-networking/security-advisories/brocade-security-advisory-2019-767 x_refsource_CONFIRMThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2019-3862
- https://www.debian.org/security/2019/dsa-4431 vendor-advisoryx_refsource_DEBIAN
- https://www.libssh2.org/CVE-2019-3862.html x_refsource_MISCVendor Advisory
- https://www.oracle.com/security-alerts/cpujan2020.html x_refsource_MISC
- https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html x_refsource_MISC
Change history (0)
No recorded changes yet.