Linux Distros Unpatched Vulnerability : CVE-2026-43464

critical Nessus Plugin ID 313324

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- net/mlx5e: RX, Fix XDP multi-buf frag counting for legacy RQ XDP multi-buf programs can modify the layout of the XDP buffer when the program calls bpf_xdp_pull_data() or bpf_xdp_adjust_tail(). The referenced commit in the fixes tag corrected the assumption in the mlx5 driver that the XDP buffer layout doesn't change during a program execution. However, this fix introduced another issue: the dropped fragments still need to be counted on the driver side to avoid page fragment reference counting issues. Such issue can be observed with the test_xdp_native_adjst_tail_shrnk_data selftest when using a payload of 3600 and shrinking by 256 bytes (an upcoming selftest patch): the last fragment gets released by the XDP code but doesn't get tracked by the driver. This results in a negative pp_ref_count during page release and the following splat: WARNING: include/net/page_pool/helpers.h:297 at mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core], CPU#12: ip/3137 Modules linked in: [...] CPU:
12 UID: 0 PID: 3137 Comm: ip Not tainted 6.19.0-rc3+ #12 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 RIP:
0010:mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core] [...] Call Trace: <TASK> mlx5e_dealloc_rx_wqe+0xcb/0x1a0 [mlx5_core] mlx5e_free_rx_descs+0x7f/0x110 [mlx5_core] mlx5e_close_rq+0x50/0x60 [mlx5_core] mlx5e_close_queues+0x36/0x2c0 [mlx5_core] mlx5e_close_channel+0x1c/0x50 [mlx5_core] mlx5e_close_channels+0x45/0x80 [mlx5_core] mlx5e_safe_switch_params+0x1a5/0x230 [mlx5_core] mlx5e_change_mtu+0xf3/0x2f0 [mlx5_core] netif_set_mtu_ext+0xf1/0x230 do_setlink.isra.0+0x219/0x1180 rtnl_newlink+0x79f/0xb60 rtnetlink_rcv_msg+0x213/0x3a0 netlink_rcv_skb+0x48/0xf0 netlink_unicast+0x24a/0x350 netlink_sendmsg+0x1ee/0x410 __sock_sendmsg+0x38/0x60 ____sys_sendmsg+0x232/0x280 ___sys_sendmsg+0x78/0xb0
__sys_sendmsg+0x5f/0xb0 [...] do_syscall_64+0x57/0xc50 This patch fixes the issue by doing page frag counting on all the original XDP buffer fragments for all relevant XDP actions (XDP_TX , XDP_REDIRECT and XDP_PASS). This is basically reverting to the original counting before the commit in the fixes tag. As frag_page is still pointing to the original tail, the nr_frags parameter to xdp_update_skb_frags_info() needs to be calculated in a different way to reflect the new nr_frags. (CVE-2026-43464)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://security-tracker.debian.org/tracker/CVE-2026-43464

Plugin Details

Severity: Critical

ID: 313324

File Name: unpatched_CVE_2026_43464.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 5/8/2026

Updated: 5/8/2026

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2026-43464

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 9

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:U/RC:C

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:linux, cpe:/o:debian:debian_linux:13.0

Required KB Items: Host/cpu, Host/local_checks_enabled, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 5/8/2026

Reference Information

CVE: CVE-2026-43464