Amazon Linux 2 : rclone (ALAS-2026-4081)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALAS-2026-4081.
##

include('compat.inc');

if (description)
{
  script_id(377945);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/11/09");

  script_cve_id("CVE-2026-78659", "CVE-2026-116189", "CVE-2026-116191");
  script_xref(name:"IAVB", value:"2026-B-0296-S");

  script_name(english:"Amazon Linux 2 : rclone (ALAS-2026-4081)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux 2 host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The version of rclone installed on the remote host is prior to 1.55.1-1. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2-2026-4081 advisory.

    rclone from 1.55.0 before 1.75.2 contains a signature verification bypass in stable selfupdate that trusts
    checksums from unsigned bytes preceding the PGP-clearsigned SHA256SUMS block. Attackers controlling the
    release distribution path can prepend an unsigned checksum line matching a malicious archive, causing
    selfupdate to install an attacker-controlled rclone executable. (CVE-2026-116189)

    Rclone before 1.75.2 contains a path traversal vulnerability in serve webdav that allows unauthenticated
    attackers to write above the served root by sending an unvalidated '..' path component. Attackers can send
    MKCOL /.. to plant a VFS node, then PUT, MOVE, COPY, or MKCOL to create, overwrite, or delete files
    belonging to other tenants. (CVE-2026-116191)

    When Trailer headers are sent by a client, the HTTP server internally uses the header values to populate
    the Request.Trailer map passed to the server handler. Because Request.Trailer is a map, each entry incurs
    memory overhead. For HTTP/2 servers, a malicious client can exploit this by sending a Trailer header
    that declares a large number of fields causing the server to allocate a disproportionate amount of memory
    while bypassing Server.MaxHeaderValueCount and Server.MaxHeaderBytes limits.This exploit is not applicable
    for HTTP/1 servers, which do not support  multiplexing a large number of requests over one TCP connection,
    and whose Server.MaxHeaderBytes are calculated differently.Server.MaxHeaderValueCount and
    Server.MaxHeaderBytes limits are now applied towards the trailer fields declared in Trailer headers.

    NOTE: https://www.openwall.com/lists/oss-security/2026/10/08/9NOTE:
    https://github.com/golang/go/issues/81857NOTE: Fixed by:
    https://github.com/golang/go/commit/cbb0fb8b51cba866018b8a0fb4b5458f16c5c80b (go1.27.2)NOTE: Fixed by:
    https://github.com/golang/go/commit/6e049521882c944afc1e519a83971ec421dc2974 (go1.26.9) (CVE-2026-78659)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com//AL2/ALAS2-2026-4081.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/faqs.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-116189.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-116191.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-78659.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update rclone' or
  or 'yum update --advisory ALAS2-2026-4081' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:C/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:L/PR:N/UI:N/S:U/C:N/I:H/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-116191");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/10/08");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/11/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/11/09");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:rclone");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:rclone-debuginfo");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info2.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/AmazonLinux/release", "Host/AmazonLinux/rpm-list");

  exit(0);
}

include("rpm2.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);

var alas_release = get_kb_item("Host/AmazonLinux/release");
if (isnull(alas_release) || !strlen(alas_release)) audit(AUDIT_OS_NOT, "Amazon Linux");
var os_ver = pregmatch(pattern: "^AL(A|\d+|-\d+)", string:alas_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Amazon Linux");
os_ver = os_ver[1];
if (os_ver != "2")
{
  if (os_ver == 'A') os_ver = 'AMI';
  audit(AUDIT_OS_NOT, "Amazon Linux 2", "Amazon Linux " + os_ver);
}

if (!get_kb_item("Host/AmazonLinux/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

var pkgs = [
    {'reference':'rclone-1.55.1-1.amzn2.0.13', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rclone-1.55.1-1.amzn2.0.13', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rclone-debuginfo-1.55.1-1.amzn2.0.13', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rclone-debuginfo-1.55.1-1.amzn2.0.13', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var reference = NULL;
  var _release = NULL;
  var sp = NULL;
  var _cpu = NULL;
  var el_string = NULL;
  var rpm_spec_vers_cmp = NULL;
  var epoch = NULL;
  var allowmaj = NULL;
  var exists_check = NULL;
  var cves = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) _release = package_array['release'];
  if (!empty_or_null(package_array['sp'])) sp = package_array['sp'];
  if (!empty_or_null(package_array['cpu'])) _cpu = package_array['cpu'];
  if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
  if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
  if (!empty_or_null(package_array['epoch'])) epoch = package_array['epoch'];
  if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
  if (!empty_or_null(package_array['exists_check'])) exists_check = package_array['exists_check'];
  if (!empty_or_null(package_array['cves'])) cves = package_array['cves'];
  if (reference && _release && (!exists_check || rpm_exists(release:_release, rpm:exists_check))) {
    if (rpm_check(release:_release, sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj, cves:cves)) flag++;
  }
}

if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "rclone / rclone-debuginfo");
}