Debian Security Advisory

DLA-2848-1 libssh2 -- LTS security update

Date Reported:
17 Dec 2021
Affected Packages:
libssh2
Vulnerable:
Yes
Security database references:
In Mitre's CVE dictionary: CVE-2019-13115, CVE-2019-17498.
More information:

Two issues have been discovered in libssh2, a client-side C library implementing the SSH2 protocol:

  • CVE-2019-13115:

    kex_method_diffie_hellman_group_exchange_sha256_key_exchange in kex.c has an integer overflow that could lead to an out-of-bounds read in the way packets are read from the server. A remote attacker who compromises a 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.

  • CVE-2019-17498:

    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.

For Debian 9 stretch, these problems have been fixed in version 1.7.0-1+deb9u2.

We recommend that you upgrade your libssh2 packages.

For the detailed security status of libssh2 please refer to its security tracker page at: https://security-tracker.debian.org/tracker/libssh2

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: https://wiki.debian.org/LTS