Unity Linux 20.1070a Security Update: kernel (UTSA-2025-394310)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(267727);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/10/15");

  script_cve_id("CVE-2024-50301");

  script_name(english:"Unity Linux 20.1070a Security Update: kernel (UTSA-2025-394310)");

  script_set_attribute(attribute:"synopsis", value:
"The Unity Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the
UTSA-2025-394310 advisory.

    In the Linux kernel, the following vulnerability has been resolved:

    security/keys: fix slab-out-of-bounds in key_task_permission

    KASAN reports an out of bounds read:
    BUG: KASAN: slab-out-of-bounds in __kuid_val include/linux/uidgid.h:36
    BUG: KASAN: slab-out-of-bounds in uid_eq include/linux/uidgid.h:63 [inline]
    BUG: KASAN: slab-out-of-bounds in key_task_permission+0x394/0x410
    security/keys/permission.c:54
    Read of size 4 at addr ffff88813c3ab618 by task stress-ng/4362

    CPU: 2 PID: 4362 Comm: stress-ng Not tainted 5.10.0-14930-gafbffd6c3ede #15
    Call Trace:
     __dump_stack lib/dump_stack.c:82 [inline]
     dump_stack+0x107/0x167 lib/dump_stack.c:123
     print_address_description.constprop.0+0x19/0x170 mm/kasan/report.c:400
     __kasan_report.cold+0x6c/0x84 mm/kasan/report.c:560
     kasan_report+0x3a/0x50 mm/kasan/report.c:585
     __kuid_val include/linux/uidgid.h:36 [inline]
     uid_eq include/linux/uidgid.h:63 [inline]
     key_task_permission+0x394/0x410 security/keys/permission.c:54
     search_nested_keyrings+0x90e/0xe90 security/keys/keyring.c:793

    This issue was also reported by syzbot.

    It can be reproduced by following these steps(more details [1]):
    1. Obtain more than 32 inputs that have similar hashes, which ends with the
       pattern '0xxxxxxxe6'.
    2. Reboot and add the keys obtained in step 1.

    The reproducer demonstrates how this issue happened:
    1. In the search_nested_keyrings function, when it iterates through the
       slots in a node(below tag ascend_to_node), if the slot pointer is meta
       and node->back_pointer != NULL(it means a root), it will proceed to
       descend_to_node. However, there is an exception. If node is the root,
       and one of the slots points to a shortcut, it will be treated as a
       keyring.
    2. Whether the ptr is keyring decided by keyring_ptr_is_keyring function.
       However, KEYRING_PTR_SUBTYPE is 0x2UL, the same as
       ASSOC_ARRAY_PTR_SUBTYPE_MASK.
    3. When 32 keys with the similar hashes are added to the tree, the ROOT
       has keys with hashes that are not similar (e.g. slot 0) and it splits
       NODE A without using a shortcut. When NODE A is filled with keys that
       all hashes are xxe6, the keys are similar, NODE A will split with a
       shortcut. Finally, it forms the tree as shown below, where slot 6 points
       to a shortcut.

                          NODE A
                  +------>+---+
          ROOT    |       | 0 | xxe6
          +---+   |       +---+
     xxxx | 0 | shortcut  :   : xxe6
          +---+   |       +---+
     xxe6 :   :   |       |   | xxe6
          +---+   |       +---+
          | 6 |---+       :   : xxe6
          +---+           +---+
     xxe6 :   :           | f | xxe6
          +---+           +---+
     xxe6 | f |
          +---+

    4. As mentioned above, If a slot(slot 6) of the root points to a shortcut,
       it may be mistakenly transferred to a key*, leading to a read
       out-of-bounds read.

    To fix this issue, one should jump to descend_to_node if the ptr is a
    shortcut, regardless of whether the node is root or not.

    [1] https://lore.kernel.org/linux-kernel/[email protected]/

    [jarkko: tweaked the commit message a bit to have an appropriate closes
     tag.]

Tenable has extracted the preceding description block directly from the Unity Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  # https://src.uniontech.com/#/security_advisory_detail?utsa_id=UTSA-2025-394310
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?0a1e5206");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2024-50301");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:C/I:N/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2024-50301");

  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:"2023/12/12");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/07/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/10/07");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

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

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

  exit(0);
}
include('rpm2.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_product = get_kb_item('installed_os/local/SSH/0/product');
if (isnull(os_product) || 'UOS Server' >!< os_product) audit(AUDIT_OS_NOT, 'UOS Server');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'UOS Server');
if (! preg(pattern:"^20.1070a([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1070a', 'UOS Server ' + os_version);

if (!get_kb_item('Host/UOS-Server/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('aarch64' >!< cpu && 'amd64' >!< cpu && 'loongarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1070a',
    'pkgs': [
      {'reference':'kernel-5.10.0-74.12', 'sp':'1070a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-74.12', 'sp':'1070a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-74.12', 'sp':'1070a', 'cpu':'loongarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-74.12', 'sp':'1070a', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  }
];

var os_release = get_one_kb_item('installed_os/local/SSH/0/release');
var os_sp = get_one_kb_item('Host/*/minor_release');

var flag = 0;
var reference;
var sp;
var _cpu;
var el_string;
var rpm_spec_vers_cmp;
var epoch;
var allowmaj;
var exists_check;
var cves;
foreach var constraint ( constraints ) {
  # Check that the target release is equal to the affected release
  if (!empty_or_null(constraint['release'])){
    if (constraint['release'] != os_release) continue;
  }
  if (!empty_or_null(constraint['sp'])){
    if (constraint['sp'] != os_sp) continue;
  }
  foreach var pkg ( constraint['pkgs'] ) {
    reference = NULL;
    sp = NULL;
    _cpu = NULL;
    el_string = NULL;
    rpm_spec_vers_cmp = NULL;
    epoch = NULL;
    allowmaj = NULL;
    exists_check = NULL;
    cves = NULL;
    if (!empty_or_null(pkg['reference'])) reference = pkg['reference'];
    if (!empty_or_null(pkg['sp'])) sp = pkg['sp'];
    if (!empty_or_null(pkg['cpu'])) _cpu = pkg['cpu'];
    if (!empty_or_null(pkg['el_string'])) el_string = pkg['el_string'];
    if (!empty_or_null(pkg['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = pkg['rpm_spec_vers_cmp'];
    if (!empty_or_null(pkg['epoch'])) epoch = pkg['epoch'];
    if (!empty_or_null(pkg['allowmaj'])) allowmaj = pkg['allowmaj'];
    if (!empty_or_null(pkg['exists_check'])) exists_check = pkg['exists_check'];
    if (!empty_or_null(pkg['cves'])) cves = pkg['cves'];
    if (reference &&
        ## (no known rpm to check OR known rpm_exists)
        (!exists_check || rpm_exists(rpm:exists_check)) &&
        rpm_check(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_WARNING,
      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, 'kernel');
}