Debian DLA-1015-1 : libgcrypt11 security update

#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory DLA-1015-1. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(101274);
  script_version("3.8");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/12/12");

  script_cve_id("CVE-2017-7526");

  script_name(english:"Debian DLA-1015-1 : libgcrypt11 security update");

  script_set_attribute(attribute:"synopsis", value:
"The remote Debian host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"It was discovered that there was a key disclosure vulnerability in
libgcrypt11 a library of cryptographic routines :

It is well known that constant-time implementations of modular
exponentiation cannot use sliding windows. However, software libraries
such as Libgcrypt, used by GnuPG, continue to use sliding windows. It
is widely believed that, even if the complete pattern of squarings and
multiplications is observed through a side-channel attack, the number
of exponent bits leaked is not sufficient to carry out a full
key-recovery attack against RSA. Specifically, 4-bit sliding windows
leak only 40% of the bits, and 5-bit sliding windows leak only 33% of
the bits.

-- Sliding right into disaster: Left-to-right sliding windows leak
<https://eprint.iacr.org/2017/627>

For Debian 7 'Wheezy', this issue has been fixed in libgcrypt11
version 1.5.0-5+deb7u6.

We recommend that you upgrade your libgcrypt11 packages.

NOTE: Tenable Network Security has extracted the preceding description
block directly from the DLA security advisory. Tenable has attempted
to automatically clean and format it as much as possible without
introducing additional issues.");
  script_set_attribute(attribute:"see_also", value:"https://eprint.iacr.org/2017/627");
  script_set_attribute(attribute:"see_also", value:"https://lists.debian.org/debian-lts-announce/2017/07/msg00007.html");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/wheezy/libgcrypt11");
  script_set_attribute(attribute:"solution", value:
"Upgrade the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2017-7526");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"patch_publication_date", value:"2017/07/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/07/07");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libgcrypt11");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libgcrypt11-dbg");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libgcrypt11-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libgcrypt11-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libgcrypt11-udeb");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:7.0");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Debian Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2017-2025 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Debian/release", "Host/Debian/dpkg-l");

  exit(0);
}


include("audit.inc");
include("debian_package.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Debian/release")) audit(AUDIT_OS_NOT, "Debian");
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;
if (deb_check(release:"7.0", prefix:"libgcrypt11", reference:"1.5.0-5+deb7u6")) flag++;
if (deb_check(release:"7.0", prefix:"libgcrypt11-dbg", reference:"1.5.0-5+deb7u6")) flag++;
if (deb_check(release:"7.0", prefix:"libgcrypt11-dev", reference:"1.5.0-5+deb7u6")) flag++;
if (deb_check(release:"7.0", prefix:"libgcrypt11-doc", reference:"1.5.0-5+deb7u6")) flag++;
if (deb_check(release:"7.0", prefix:"libgcrypt11-udeb", reference:"1.5.0-5+deb7u6")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:deb_report_get());
  else security_warning(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");