Description
An integer overflow flaw which could lead to an out of bounds write was discovered in libssh2 before 1.8.1 in the way packets are read from the server. A remote attacker who compromises a SSH server may be able to execute code on the client system when a user connects to the server.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| The libssh2 Project | libssh2 | 1.8.1 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | libssh2 | 1.8.0-2.1 | — |
| Debian 13 | libssh2 | 1.8.0-2.1 | — |
| Debian 12 | libssh2 | 1.8.0-2.1 | — |
| Debian 9 | libssh2 | 1.7.0-1+deb9u1 | DSA-4431-1 |
| Debian 8 | libssh2 | 1.4.3-4.1+deb8u2 | DLA-1730-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | libssh2 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | libssh2 | 1.5.0-2ubuntu0.1+esm1 | USN-5308-1 |
| Ubuntu Pro 14.04 LTS | libssh2 | 1.4.3-2ubuntu0.2+esm1 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | SLOF | 20171214-5.gitfa98132.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | hivex +4 | 1.3.15-6.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | libguestfs-winsupport | 8.0-2.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | libiscsi +2 | 1.18.0-6.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | libssh2 | 1.8.0-7.module+el8.0.0+3075+09be6b65.1 | RHSA-2019:1175 |
| RHEL 8 | libvirt +27 | 4.5.0-23.1.module+el8.0.0+3151+3ba813f9 | RHSA-2019:1175 |
| RHEL 8 | libvirt-dbus | 1.2.0-2.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | libvirt-python +1 | 4.5.0-1.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | nbdkit +9 | 1.4.2-4.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | netcf +2 | 0.2.8-10.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | perl-Sys-Virt | 4.5.0-4.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | qemu-img +9 | 15:2.12.0-64.module+el8.0.0+3180+d6a3561d.2 | RHSA-2019:1175 |
| RHEL 8 | seabios +2 | 1.11.1-3.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | sgabios +1 | 1:0.20170427git-2.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | supermin +1 | 5.1.19-8.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 8 | virt-dib +24 | 1:1.38.4-10.module+el8.0.0+3075+09be6b65 | RHSA-2019:1175 |
| RHEL 7 | libssh2 +2 | 1.4.3-12.el7_6.2 | RHSA-2019:0679 |
| RHEL 6 | libssh2 +2 | 1.4.2-3.el6_10.1 | RHSA-2019:1652 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7.5 EUS | libssh2 +2 | 1.4.3-11.el7_5.1 | RHSA-2019:1791 |
| RHEL 7.4 EUS | libssh2 +2 | 1.4.3-11.el7_4.1 | RHSA-2019:1943 |
| RHEL 7.3 TUS | libssh2 +2 | 1.4.3-11.el7_3.1 | RHSA-2019:2399 |
| RHEL 7.3 E4S | libssh2 +2 | 1.4.3-11.el7_3.1 | RHSA-2019:2399 |
| RHEL 7.3 AUS | libssh2 +2 | 1.4.3-11.el7_3.1 | RHSA-2019:2399 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP2 | libssh2_org | 1.9.0-4.13.1 | SUSE-SU-2020:3551-1 |
| SLES 15 SP1 | libssh2_org | 1.9.0-4.13.1 | SUSE-SU-2020:3551-1 |
| SLES 15 | libssh2_org | 1.9.0-4.13.1 | SUSE-SU-2020:3551-1 |
| SLES 12 SP4 | libssh2_org | 1.4.3-20.3.1 | SUSE-SU-2019:0655-1 |
| SLES 12 SP3 | libssh2_org | 1.4.3-20.3.1 | SUSE-SU-2019:0655-1 |
Show 14 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | libssh2_org | 1.4.3-20.3.1 | SUSE-SU-2019:0655-1 |
| SLES 12 SP1 | libssh2_org | 1.4.3-20.3.1 | SUSE-SU-2019:0655-1 |
| SLES 12 | libssh2_org | 1.4.3-20.3.1 | SUSE-SU-2019:0655-1 |
| SLES 11 SP4 | libssh2_org | 1.4.3-17.3.1 | SUSE-SU-2019:13982-1 |
| SLES for SAP 15 | libssh2_org | 1.9.0-4.13.1 | SUSE-SU-2020:3551-1 |
| SLES for SAP 12 SP4 | libssh2_org | 1.4.3-20.3.1 | SUSE-SU-2019:0655-1 |
| SLES for SAP 12 SP3 | libssh2_org | 1.4.3-20.3.1 | SUSE-SU-2019:0655-1 |
| SLES for SAP 12 SP2 | libssh2_org | 1.4.3-20.3.1 | SUSE-SU-2019:0655-1 |
| SLES for SAP 12 SP1 | libssh2_org | 1.4.3-20.3.1 | SUSE-SU-2019:0655-1 |
| SLES for SAP 11 SP4 | libssh2_org | 1.4.3-17.3.1 | SUSE-SU-2019:13982-1 |
| SLE HPC 15 | libssh2_org | 1.9.0-4.13.1 | SUSE-SU-2020:3551-1 |
| SUSE OpenStack Cloud 7 | libssh2_org | 1.4.3-20.3.1 | SUSE-SU-2019:0655-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | libssh2_org | 1.2.9-4.2.12.5.1 | SUSE-SU-2019:13997-1 |
| SUSE Enterprise Storage 4 | libssh2_org | 1.4.3-20.3.1 | SUSE-SU-2019:0655-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libssh2_org | 1.9.0-3.6 | openSUSE-SU-2024:10999-1 |
| openSUSE Leap 15.2 | libssh2_org | 1.9.0-lp152.8.3.1 | openSUSE-SU-2020:2129-1 |
| openSUSE Leap 15.1 | libssh2_org | 1.9.0-lp151.6.6.1 | openSUSE-SU-2020:2126-1 |
| openSUSE Leap 15.0 | libssh2_org | 1.8.0-lp150.3.3.1 | openSUSE-SU-2019:1109-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.23 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.22 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.21 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.20 | libssh2 | 1.8.1-r0 | — |
Show 11 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.18 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.17 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.16 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.15 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.14 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.13 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.12 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.11 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.10 | libssh2 | 1.8.1-r0 | — |
| Alpine v3.9 | libssh2 | 1.8.1-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | libssh2 +2 | 1.4.3-12.amzn2.2 | ALAS2-2019-1199 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | hivex +4 | 1.3.15-6.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | libguestfs-winsupport | 8.0-2.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | libiscsi +2 | 1.18.0-6.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | libssh2 | 1.8.0-7.module+el8.0.0+5219+3c0c6858.1 | ELSA-2019-1175 |
| Oracle Linux 8 | libvirt +27 | 4.5.0-23.1.0.1.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | libvirt-dbus | 1.2.0-2.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | nbdkit +9 | 1.4.2-4.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | netcf +2 | 0.2.8-10.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | perl-Sys-Virt | 4.5.0-4.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | python3-libvirt | 4.5.0-1.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | qemu-img +9 | 15:2.12.0-64.module+el8.0.0+5219+3c0c6858.2 | ELSA-2019-1175 |
| Oracle Linux 8 | seabios +2 | 1.11.1-3.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | sgabios +1 | 1:0.20170427git-2.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | supermin +1 | 5.1.19-8.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 8 | virt-dib +24 | 1:1.38.4-10.0.1.module+el8.0.0+5219+3c0c6858 | ELSA-2019-1175 |
| Oracle Linux 7 | libssh2 +2 | 1.4.3-12.el7_6.2 | ELSA-2019-0679 |
Advisories 23
- RHSA-2019:2399 Red Hat Security Advisory: libssh2 security update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- RHSA-2019:1943 Red Hat Security Advisory: libssh2 security update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- RHSA-2019:1791 Red Hat Security Advisory: libssh2 security update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- RHSA-2019:1652 Red Hat Security Advisory: libssh2 security update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- RHSA-2019:1175 Red Hat Security Advisory: virt:rhel security update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- RHSA-2019:0679 Red Hat Security Advisory: libssh2 security update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- SSA-398330 SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5 Siemens ProductCERT · Oct 13, 2026
- USN-5308-1 libssh2 vulnerabilities Ubuntu Security Notices (USN) · Jun 25, 2026
- DSA-4431-1 libssh2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1730-1 libssh2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2019:13982-1 Security update for libssh2_org SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:2129-1 Security update for libssh2_org SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:0655-1 Security update for libssh2_org SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:3551-1 Security update for libssh2_org SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:2126-1 Security update for libssh2_org SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:1109-1 Security update for libssh2_org SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:13997-1 Security update for libssh2_org SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10999-1 libssh2-1-1.9.0-3.6 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- ICSA-23-348-10 Siemens SIMATIC S7-1500 CISA ICS & IT advisories · Aug 12, 2025
- WID-SEC-2023-1230 libssh2: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jan 14, 2025
- ELSA-2019-1175 Important: virt:ol security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Jul 30, 2019
- ALAS2-2019-1199 Important: libssh2 security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Apr 26, 2019
- ELSA-2019-0679 Important: libssh2 security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Mar 28, 2019
References
- [oss-security] 20190318 [SECURITY ADVISORIES] libssh2 mailing-list
- 20190319 [slackware-security] libssh2 (SSA:2019-077-01) mailing-list
- https://www.libssh2.org/CVE-2019-3855.html
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3855
- http://packetstormsecurity.com/files/152136/Slackware-Security-Advisory-libssh2-Updates.html
- 107485 vdb-entry
- FEDORA-2019-f31c14682f vendor-advisory
- https://www.broadcom.com/support/fibre-channel-networking/security-advisories/brocade-security-advisory-2019-767
- [debian-lts-announce] 20190326 [SECURITY] [DLA 1730-1] libssh2 security update mailing-list
- https://security.netapp.com/advisory/ntap-20190327-0005/
- RHSA-2019:0679 vendor-advisory
- openSUSE-SU-2019:1075 vendor-advisory
- openSUSE-SU-2019:1109 vendor-advisory
- FEDORA-2019-3348cb4934 vendor-advisory
- DSA-4431 vendor-advisory
- 20190415 [SECURITY] [DSA 4431-1] libssh2 security update mailing-list
- RHSA-2019:1175 vendor-advisory
- RHSA-2019:1652 vendor-advisory
- RHSA-2019:1791 vendor-advisory
- RHSA-2019:1943 vendor-advisory
- FEDORA-2019-9d85600fc7 vendor-advisory
- FEDORA-2019-5885663621 vendor-advisory
- RHSA-2019:2399 vendor-advisory
- https://support.apple.com/kb/HT210609
- 20190927 APPLE-SA-2019-9-26-7 Xcode 11.0 mailing-list
- 20190927 APPLE-SA-2019-9-26-7 Xcode 11.0 mailing-list
- https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html