5.9 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
6.9 Medium
AI Score
Confidence
High
0.963 High
EPSS
Percentile
99.5%
The version of libssh installed on the remote host is prior to 0.10.6. It is, therefore, affected by multiple vulnerabilities as referenced in the SSA:2023-353-01 advisory.
The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attackers to bypass integrity checks such that some packets are omitted (from the extension negotiation message), and a client and server may consequently end up with a connection for which some security features have been downgraded or disabled, aka a Terrapin attack. This occurs because the SSH Binary Packet Protocol (BPP), implemented by these extensions, mishandles the handshake phase and mishandles use of sequence numbers. For example, there is an effective attack against SSH’s use of ChaCha20-Poly1305 (and CBC with Encrypt-then-MAC). The bypass occurs in [email protected] and (if CBC is used) the [email protected] MAC algorithms. This also affects Maverick Synergy Java SSH API before 3.1.0-SNAPSHOT, Dropbear through 2022.83, Ssh before 5.1.1 in Erlang/OTP, PuTTY before 0.80, AsyncSSH before 2.14.2, golang.org/x/crypto before 0.17.0, libssh before 0.10.6, libssh2 through 1.11.0, Thorn Tech SFTP Gateway before 3.4.6, Tera Term before 5.1, Paramiko before 3.4.0, jsch before 0.2.15, SFTPGo before 2.5.6, Netgate pfSense Plus through 23.09.1, Netgate pfSense CE through 2.7.2, HPN-SSH through 18.2.0, ProFTPD 1.3.9rc1, ORYX CycloneSSH before 2.3.4, NetSarang XShell 7 before Build 0144, CrushFTP before 10.6.0, ConnectBot SSH library before 2.2.22, the mscdex ssh2 module before 1.15.0 for Node.js, the thrussh library before 0.35.1 for Rust, and the Russh crate before 0.40.2 for Rust; and there could be effects on Bitvise SSH through 9.31. (CVE-2023-48795)
A flaw was found in the libssh implements abstract layer for message digest (MD) operations implemented by different supported crypto backends. The return values from these were not properly checked, which could cause low-memory situations failures, NULL dereferences, crashes, or usage of the uninitialized memory as an input for the KDF. In this case, non-matching keys will result in decryption/integrity failures, terminating the connection. (CVE-2023-6918)
Note that Nessus has not tested for these issues but has instead relied only on the application’s self-reported version number.
#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##
#
# The descriptive text and package checks in this plugin were
# extracted from Slackware Security Advisory SSA:2023-353-01. The text
# itself is copyright (C) Slackware Linux, Inc.
##
include('compat.inc');
if (description)
{
script_id(187107);
script_version("1.7");
script_set_attribute(attribute:"plugin_modification_date", value:"2024/01/17");
script_cve_id("CVE-2023-6004", "CVE-2023-6918", "CVE-2023-48795");
script_xref(name:"IAVA", value:"2023-A-0703");
script_name(english:"Slackware Linux 14.2 / 15.0 / current libssh Multiple Vulnerabilities (SSA:2023-353-01)");
script_set_attribute(attribute:"synopsis", value:
"The remote Slackware Linux host is missing a security update to libssh.");
script_set_attribute(attribute:"description", value:
"The version of libssh installed on the remote host is prior to 0.10.6. It is, therefore, affected by multiple
vulnerabilities as referenced in the SSA:2023-353-01 advisory.
- The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other
products, allows remote attackers to bypass integrity checks such that some packets are omitted (from the
extension negotiation message), and a client and server may consequently end up with a connection for
which some security features have been downgraded or disabled, aka a Terrapin attack. This occurs because
the SSH Binary Packet Protocol (BPP), implemented by these extensions, mishandles the handshake phase and
mishandles use of sequence numbers. For example, there is an effective attack against SSH's use of
ChaCha20-Poly1305 (and CBC with Encrypt-then-MAC). The bypass occurs in [email protected] and
(if CBC is used) the [email protected] MAC algorithms. This also affects Maverick Synergy Java SSH API
before 3.1.0-SNAPSHOT, Dropbear through 2022.83, Ssh before 5.1.1 in Erlang/OTP, PuTTY before 0.80,
AsyncSSH before 2.14.2, golang.org/x/crypto before 0.17.0, libssh before 0.10.6, libssh2 through 1.11.0,
Thorn Tech SFTP Gateway before 3.4.6, Tera Term before 5.1, Paramiko before 3.4.0, jsch before 0.2.15,
SFTPGo before 2.5.6, Netgate pfSense Plus through 23.09.1, Netgate pfSense CE through 2.7.2, HPN-SSH
through 18.2.0, ProFTPD 1.3.9rc1, ORYX CycloneSSH before 2.3.4, NetSarang XShell 7 before Build 0144,
CrushFTP before 10.6.0, ConnectBot SSH library before 2.2.22, the mscdex ssh2 module before 1.15.0 for
Node.js, the thrussh library before 0.35.1 for Rust, and the Russh crate before 0.40.2 for Rust; and there
could be effects on Bitvise SSH through 9.31. (CVE-2023-48795)
- A flaw was found in the libssh implements abstract layer for message digest (MD) operations implemented by
different supported crypto backends. The return values from these were not properly checked, which could
cause low-memory situations failures, NULL dereferences, crashes, or usage of the uninitialized memory as
an input for the KDF. In this case, non-matching keys will result in decryption/integrity failures,
terminating the connection. (CVE-2023-6918)
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
# http://www.slackware.com/security/viewer.php?l=slackware-security&y=2023&m=slackware-security.394037
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?babc1914");
script_set_attribute(attribute:"solution", value:
"Upgrade the affected libssh package.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:N/C:N/I:C/A:N");
script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N");
script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2023-48795");
script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
script_set_attribute(attribute:"exploit_available", value:"true");
script_set_attribute(attribute:"vuln_publication_date", value:"2023/12/18");
script_set_attribute(attribute:"patch_publication_date", value:"2023/12/19");
script_set_attribute(attribute:"plugin_publication_date", value:"2023/12/19");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:slackware:slackware_linux:libssh");
script_set_attribute(attribute:"cpe", value:"cpe:/o:slackware:slackware_linux");
script_set_attribute(attribute:"cpe", value:"cpe:/o:slackware:slackware_linux:14.2");
script_set_attribute(attribute:"cpe", value:"cpe:/o:slackware:slackware_linux:15.0");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_set_attribute(attribute:"stig_severity", value:"II");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Slackware Local Security Checks");
script_copyright(english:"This script is Copyright (C) 2023-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ssh_get_info.nasl");
script_require_keys("Host/local_checks_enabled", "Host/Slackware/release", "Host/Slackware/packages");
exit(0);
}
include("slackware.inc");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Slackware/release")) audit(AUDIT_OS_NOT, "Slackware");
if (!get_kb_item("Host/Slackware/packages")) audit(AUDIT_PACKAGE_LIST_MISSING);
var cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Slackware", cpu);
var flag = 0;
var constraints = [
{ 'fixed_version' : '0.10.6', 'product' : 'libssh', 'os_name' : 'Slackware Linux', 'os_version' : '14.2', 'service_pack' : '1_slack14.2', 'arch' : 'i586' },
{ 'fixed_version' : '0.10.6', 'product' : 'libssh', 'os_name' : 'Slackware Linux', 'os_version' : '14.2', 'service_pack' : '1_slack14.2', 'arch' : 'x86_64' },
{ 'fixed_version' : '0.10.6', 'product' : 'libssh', 'os_name' : 'Slackware Linux', 'os_version' : '15.0', 'service_pack' : '1_slack15.0', 'arch' : 'i586' },
{ 'fixed_version' : '0.10.6', 'product' : 'libssh', 'os_name' : 'Slackware Linux', 'os_version' : '15.0', 'service_pack' : '1_slack15.0', 'arch' : 'x86_64' },
{ 'fixed_version' : '0.10.6', 'product' : 'libssh', 'os_name' : 'Slackware Linux', 'os_version' : 'current', 'service_pack' : '1', 'arch' : 'i586' },
{ 'fixed_version' : '0.10.6', 'product' : 'libssh', 'os_name' : 'Slackware Linux', 'os_version' : 'current', 'service_pack' : '1', 'arch' : 'x86_64' }
];
foreach var constraint (constraints) {
var pkg_arch = constraint['arch'];
var arch = NULL;
if (pkg_arch == "x86_64") {
arch = pkg_arch;
}
if (slackware_check(osver:constraint['os_version'],
arch:arch,
pkgname:constraint['product'],
pkgver:constraint['fixed_version'],
pkgarch:pkg_arch,
pkgnum:constraint['service_pack'])) flag++;
}
if (flag)
{
security_report_v4(
port : 0,
severity : SECURITY_WARNING,
extra : slackware_report_get()
);
exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");
Vendor | Product | Version | CPE |
---|---|---|---|
slackware | slackware_linux | libssh | p-cpe:/a:slackware:slackware_linux:libssh |
slackware | slackware_linux | cpe:/o:slackware:slackware_linux | |
slackware | slackware_linux | 14.2 | cpe:/o:slackware:slackware_linux:14.2 |
slackware | slackware_linux | 15.0 | cpe:/o:slackware:slackware_linux:15.0 |
5.9 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
6.9 Medium
AI Score
Confidence
High
0.963 High
EPSS
Percentile
99.5%