Linux Distros Unpatched Vulnerability : CVE-2026-74489

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

include('compat.inc');

if (description)
{
  script_id(335880);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/15");

  script_cve_id("CVE-2026-74489");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-74489");

  script_set_attribute(attribute:"synopsis", value:
"The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be
patched.");
  script_set_attribute(attribute:"description", value:
"The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied
patch available.

  - wifi: mac80211: fix tid_tx use-after-free on BA session stop ieee80211_stop_tx_ba_cb() hands tid_tx to
    kfree_rcu() through ieee80211_remove_tid_tx(), and then reads tid_tx->ndp after dropping sta->lock:
    ieee80211_remove_tid_tx(sta, tid); /* kfree_rcu(tid_tx, rcu_head) */ ... spin_unlock_bh(&sta->lock); if
    (start_txq) ieee80211_agg_start_txq(sta, tid, false); if (send_delba) ieee80211_send_delba(...,
    tid_tx->ndp); That read is not covered by an RCU read-side critical section, and it runs in preemptible
    process context: both callers hold the wiphy mutex, reaching it either from the
    ieee80211_ba_session_work() wiphy work or from ieee80211_sta_tear_down_BA_sessions() during station
    teardown. Softirqs can run in that window too, both from the local_bh_enable() that ends
    ieee80211_agg_start_txq() and from any interrupt exit, so the RCU callback can free tid_tx before the
    read. Driving the function from a test module with the grace period forced into that window, KASAN reports
    the read, and the free arrives on the ordinary RCU softirq path: BUG: KASAN: slab-use-after-free in
    ieee80211_stop_tx_ba_cb+0x3cd/0x400 Read of size 1 at addr ffff888002b9f52e by task kworker/0:1/10 [...]
    Freed by task 57: __kasan_slab_free+0x47/0x70 __rcu_free_sheaf_prepare+0x70/0x250
    rcu_free_sheaf_nobarn+0x18/0x40 rcu_core+0x426/0x1310 handle_softirqs+0x144/0x590
    __irq_exit_rcu+0xea/0x150 irq_exit_rcu+0x9/0x20 sysvec_apic_timer_interrupt+0x6b/0x80
    asm_sysvec_apic_timer_interrupt+0x1a/0x20 send_delba is only set when tx_stop is set, which happens for
    AGG_STOP_LOCAL_REQUEST alone, so this is reached on local teardown - session idle timeout, PTK rekey,
    suspend, HW reconfig - and not from a peer's DELBA. Read ndp into a local before the session is freed,
    while sta->lock is still held. tid_tx->ndp has a single writer, in ieee80211_tx_ba_session_handle_start(),
    which cannot run concurrently here: both paths are serialised by the wiphy mutex, and the session is
    already marked HT_AGG_STATE_STOPPING at this point. tid_tx->ndp is also the only tid_tx dereference left
    after ieee80211_remove_tid_tx() in this function. [move/change the comment a bit to be more general not
    just on ndp, initialize ndp directly] (CVE-2026-74489)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-74489");
  script_set_attribute(attribute:"solution", value:
"There is no known solution at this time.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-74489");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/08/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/15");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:14.0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:linux");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Misc.");

  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", "set_linux_os_id.nasl");
  script_require_keys("Host/cpu", "Host/local_checks_enabled", "global_settings/vendor_unpatched", "Host/OS/identifier");
  script_require_ports("Host/OS/Debian Linux-14");

  exit(0);
}

if (!get_kb_item("global_settings/vendor_unpatched")) exit(0, "Unpatched Vulnerabilities Detection not active.");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (empty_or_null(get_one_kb_item("Host/Debian/dpkg-l"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "Debian Linux-14": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14",
        "pkgs": [
          {"reference": "bpftool"},
          {"reference": "hyperv-daemons"},
          {"reference": "intel-sdsi"},
          {"reference": "libcpupower-dev"},
          {"reference": "libcpupower1"},
          {"reference": "linux-base-7.1.7+deb14-alpha-generic"},
          {"reference": "linux-base-7.1.7+deb14-alpha-smp"},
          {"reference": "linux-base-7.1.7+deb14-amd64"},
          {"reference": "linux-base-7.1.7+deb14-arm64"},
          {"reference": "linux-base-7.1.7+deb14-arm64-16k"},
          {"reference": "linux-base-7.1.7+deb14-armmp"},
          {"reference": "linux-base-7.1.7+deb14-armmp-lpae"},
          {"reference": "linux-base-7.1.7+deb14-cloud-amd64"},
          {"reference": "linux-base-7.1.7+deb14-cloud-arm64"},
          {"reference": "linux-base-7.1.7+deb14-loong64"},
          {"reference": "linux-base-7.1.7+deb14-m68k"},
          {"reference": "linux-base-7.1.7+deb14-parisc"},
          {"reference": "linux-base-7.1.7+deb14-parisc64"},
          {"reference": "linux-base-7.1.7+deb14-powerpc"},
          {"reference": "linux-base-7.1.7+deb14-powerpc-smp"},
          {"reference": "linux-base-7.1.7+deb14-powerpc64"},
          {"reference": "linux-base-7.1.7+deb14-powerpc64-64k"},
          {"reference": "linux-base-7.1.7+deb14-powerpc64le"},
          {"reference": "linux-base-7.1.7+deb14-powerpc64le-64k"},
          {"reference": "linux-base-7.1.7+deb14-riscv64"},
          {"reference": "linux-base-7.1.7+deb14-rt-amd64"},
          {"reference": "linux-base-7.1.7+deb14-rt-arm64"},
          {"reference": "linux-base-7.1.7+deb14-s390x"},
          {"reference": "linux-base-7.1.7+deb14-sh7751r"},
          {"reference": "linux-base-7.1.7+deb14-sparc64"},
          {"reference": "linux-base-7.1.7+deb14-sparc64-smp"},
          {"reference": "linux-base-7.1.7+deb14-test"}
        ]
      }
    ]
  }
};

var distro_constraints_values = linux_unpatched::get_distro_constraints(distro_constraints_arr:distro_constraints_array);
if (empty_or_null(distro_constraints_values)) audit(AUDIT_HOST_NOT, 'affected');

var third_party_support = get_kb_item('Host/OS/extended-third-party');
if (!empty_or_null(third_party_support)) {
    var third_party_vendors = distro_constraints_values['third_party'];
    if (!empty_or_null(third_party_vendors)) {
        var vendor;
        foreach vendor (third_party_vendors) {
            if (vendor == third_party_support) exit(0, 'A third party management patch is available for this vulnerability from ' + vendor + '.\n');
        }
    }
}

var report = linux_unpatched::check_unpatched_constraints(distro_constraints_values:distro_constraints_values);

if (!empty_or_null(report))
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : report
  );
  exit(0);
}
else
{
  audit(AUDIT_HOST_NOT, 'affected');
}