CVE-2019-17498
Published: 21 October 2019
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.
From the Ubuntu Security Team
It was discovered that libssh2 incorrectly handled bound checks in SSH_MSG_DISCONNECT. A remote attacker could possibly use this issue to cause a denial of service or obtain sensitive information.
Priority
Status
Package | Release | Status |
---|---|---|
libssh2
Launchpad, Ubuntu, Debian |
bionic |
Needed
|
disco |
Ignored
(end of life)
|
|
eoan |
Ignored
(end of life)
|
|
focal |
Needed
|
|
groovy |
Ignored
(end of life)
|
|
hirsute |
Not vulnerable
(1.9.0-1)
|
|
impish |
Not vulnerable
(1.9.0-1)
|
|
jammy |
Not vulnerable
(1.9.0-1)
|
|
kinetic |
Not vulnerable
(1.9.0-1)
|
|
lunar |
Not vulnerable
(1.9.0-1)
|
|
mantic |
Not vulnerable
(1.9.0-1)
|
|
noble |
Not vulnerable
(1.9.0-1)
|
|
trusty |
Released
(1.4.3-2ubuntu0.2+esm2)
Available with Ubuntu Pro or Ubuntu Pro (Infra-only) |
|
upstream |
Released
(1.9.0-1, 1.4.3-4.1+deb8u6)
|
|
xenial |
Released
(1.5.0-2ubuntu0.1+esm1)
Available with Ubuntu Pro |
|
Patches:
upstream: https://github.com/libssh2/libssh2/pull/402/commits/1c6fa92b77e34d089493fe6d3e2c6c8775858b94 |
Severity score breakdown
Parameter | Value |
---|---|
Base score | 8.1 |
Attack vector | Network |
Attack complexity | Low |
Privileges required | None |
User interaction | Required |
Scope | Unchanged |
Confidentiality | High |
Integrity impact | None |
Availability impact | High |
Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H |
References
- 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
- https://github.com/libssh2/libssh2/blob/42d37aa63129a1b2644bf6495198923534322d64/src/packet.c#L480
- https://github.com/libssh2/libssh2/pull/402/commits/1c6fa92b77e34d089493fe6d3e2c6c8775858b94
- https://ubuntu.com/security/notices/USN-5308-1
- https://www.cve.org/CVERecord?id=CVE-2019-17498
- NVD
- Launchpad
- Debian