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.
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 | 1.9.0-1 | — |
| Debian 13 | libssh2 | 1.9.0-1 | — |
| Debian 12 | libssh2 | 1.9.0-1 | — |
| Debian 10 | libssh2 | 1.8.0-2.1+deb10u1 | DLA-3559-1 |
| Debian 9 | libssh2 | 1.7.0-1+deb9u2 | DLA-2848-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 8 | libssh2 | 1.4.3-4.1+deb8u6 | DLA-1991-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | libssh2 | No fix yet | — |
| Ubuntu Pro 18.04 LTS | libssh2 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | libssh2 | 1.5.0-2ubuntu0.1+esm1 | USN-5308-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 14.04 LTS | libssh2 | 1.4.3-2ubuntu0.2+esm2 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | libssh2 +2 | 1.8.0-4.el7 | RHSA-2020:3915 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP5 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLES 15 SP4 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLES 15 SP3 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLES 15 SP2 | libssh2_org | 1.9.0-4.13.1 | SUSE-SU-2020:3551-1, SUSE-RU-2023:4192-1 |
| SLES 15 SP1 | libssh2_org | 1.9.0-4.13.1 | SUSE-SU-2020:3551-1, SUSE-RU-2023:4192-1 |
Show 34 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 | libssh2_org | 1.8.0-4.10.1 | SUSE-SU-2020:3551-1, SUSE-SU-2019:2900-2, SUSE-SU-2019:2900-1 |
| SLES 12 SP5 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1, SUSE-RU-2023:4066-1 |
| SLES 12 SP4 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SLES 12 SP3 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SLES 12 SP2 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SLES 12 SP1 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SLES 11 SP4 | libssh2_org | 1.4.3-17.12.1 | SUSE-SU-2019:14206-1 |
| SLES for SAP 15 SP3 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLES for SAP 15 SP2 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLES for SAP 15 SP1 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLES for SAP 15 | libssh2_org | 1.8.0-4.10.1 | SUSE-SU-2020:3551-1, SUSE-SU-2019:2900-2 |
| SLES for SAP 12 SP5 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1, SUSE-RU-2023:4066-1 |
| SLES for SAP 12 SP4 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SLES for SAP 12 SP3 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SLES for SAP 12 SP2 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SLES for SAP 12 SP1 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SLE Micro 5.5 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLE Micro 5.4 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLE Micro 5.3 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLE Micro 5.2 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLE Micro 5.1 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLE HPC 15 SP3 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLE HPC 15 SP2 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLE HPC 15 SP1 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SLE HPC 15 | libssh2_org | 1.8.0-4.10.1 | SUSE-SU-2020:3551-1, SUSE-SU-2019:2900-2 |
| SUSE OpenStack Cloud Crowbar 8 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SUSE OpenStack Cloud 8 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SUSE OpenStack Cloud 7 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SUSE Manager Server 4.2 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SUSE Manager Proxy 4.2 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | libssh2_org | 1.2.9-4.2.12.18.1 | SUSE-SU-2019:14226-1 |
| SUSE HPE Helion OpenStack 8 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
| SUSE Enterprise Storage 7.1 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| SUSE Enterprise Storage 5 | libssh2_org | 1.4.3-20.14.1 | SUSE-SU-2019:2936-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libssh2_org | 1.9.0-3.6 | openSUSE-SU-2024:10999-1 |
| openSUSE Leap 15.5 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| openSUSE Leap 15.4 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| openSUSE Leap 15.2 | libssh2_org | 1.9.0-lp152.8.3.1 | openSUSE-SU-2020:2129-1 |
| openSUSE Leap 15.1 | libssh2_org | 1.8.0-lp151.6.3.1 | openSUSE-SU-2020:2126-1, openSUSE-SU-2019:2483-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap Micro 5.4 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
| openSUSE Leap Micro 5.3 | libssh2_org | 1.11.0-150000.4.19.1 | SUSE-RU-2023:4192-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.23 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.22 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.21 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.20 | libssh2 | 1.9.0-r1 | — |
Show 11 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.18 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.17 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.16 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.15 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.14 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.13 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.12 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.11 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.10 | libssh2 | 1.9.0-r1 | — |
| Alpine v3.9 | libssh2 | 1.9.0-r1 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | libssh2 +2 | 1.4.3-12.amzn2.2.3 | ALAS2-2020-1531 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | libssh2 | 1.9.0-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | libssh2 +2 | 1.8.0-4.el7 | ELSA-2020-3915 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
GitHub 1 repository
-
Timon-L/3007Project ★ 0 · Oct 9, 2022
Secure coding project, research on CVE-2019-17498 and implement a player score function written in C.
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 24
- RHSA-2020:3915 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
- DLA-2848-1 libssh2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-3559-1 libssh2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1991-1 libssh2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-RU-2023:4066-1 Recommended update for libssh2_org SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:14226-1 Security update for libssh2_org SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:2936-1 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-2019:2900-2 Security update for libssh2_org SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-RU-2023:4192-1 Recommended 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-2019:2483-1 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-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
- VDE-2022-010 PHOENIX CONTACT: Multiple Linux component vulnerabilities fixed in latest AXC F x152 LTS release CERT@VDE · May 22, 2025
- SUSE-SU-2019:14206-1 Security update for libssh2_org SUSE / openSUSE Security Updates · May 2, 2025
- SUSE-SU-2019:2900-1 Security update for libssh2_org SUSE / openSUSE Security Updates · May 2, 2025
- WID-SEC-2023-2695 Oracle Health Sciences Applications: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 17, 2023
- WID-SEC-2022-1363 libssh2: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Sep 10, 2023
- ALAS2-2020-1531 Moderate: libssh2 security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Oct 22, 2020
- ELSA-2020-3915 Moderate: libssh2 security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Oct 6, 2020
References
- https://github.com/libssh2/libssh2/blob/42d37aa63129a1b2644bf6495198923534322d64/src/packet.c#L480
- 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
- FEDORA-2019-91529f19e4 vendor-advisory
- openSUSE-SU-2019:2483 vendor-advisory
- [debian-lts-announce] 20191113 [SECURITY] [DLA 1991-1] libssh2 security update mailing-list
- FEDORA-2019-ec04c34768 vendor-advisory
- https://github.com/libssh2/libssh2/commit/dedcbd106f8e52d5586b0205bc7677e4c9868f9c
- [debian-lts-announce] 20211217 [SECURITY] [DLA 2848-1] libssh2 security update mailing-list
- https://security.netapp.com/advisory/ntap-20220909-0004/
- http://packetstormsecurity.com/files/172835/libssh2-1.9.0-Out-Of-Bounds-Read.html
- [debian-lts-announce] 20230908 [SECURITY] [DLA 3559-1] libssh2 security update mailing-list