- -------------------------------------------------------------------------
Debian LTS Advisory DLA-2848-1                [email protected]
https://www.debian.org/lts/security/                         Anton Gladky
December 17, 2021                             https://wiki.debian.org/LTS
- -------------------------------------------------------------------------

Package        : libssh2
Version        : 1.7.0-1+deb9u2
CVE ID         : CVE-2019-13115 CVE-2019-17498

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