Linux Distros Unpatched Vulnerability : CVE-2026-74465

high Nessus Plugin ID 335890

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: openvswitch: fix potential UAF on meter attach failure While attaching a newly created meter attach_meter() function makes the new meter visible to other CPUs but can still fail afterwards. On failure, it detaches the meter back and returns an error. However, this is an unexpected behavior for the ovs_meter_cmd_set() that uses a plain kfree(meter) on attach failure without waiting for RCU readers to stop using it, assuming it was never visible. This is never a problem for ovs-vswitchd as it always creates meters before creating any flows that use them. But the UAF can be triggered with a custom application using uAPI: BUG: KASAN: slab-use-after-free in ovs_meter_execute (net/openvswitch/meter.c:653) Read of size 8 at addr ffff88810d152650 by task meter/2508 Call Trace: ovs_meter_execute (net/openvswitch/meter.c:653) do_execute_actions (net/openvswitch/actions.c:1407) ovs_execute_actions (net/openvswitch/actions.c:1584) ovs_packet_cmd_execute (net/openvswitch/datapath.c:703) ...
netlink_sendmsg (af_netlink.c:1900) Allocated by task 2519: __kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415) ovs_meter_cmd_set (net/openvswitch/meter.c:422) ... netlink_sendmsg (af_netlink.c:1900) Freed by task 2519: kfree (mm/slub.c:2705 mm/slub.c:6405 mm/slub.c:6720) ovs_meter_cmd_set (net/openvswitch/meter.c:479) ... netlink_sendmsg (af_netlink.c:1900) Fix that by making sure attach_meter() doesn't make the meter visible until all the checks are done and the function can't fail anymore. This also makes sure the hash value is calculated after the potential re-sizing of the table. Reported by Trend Micro's Zero Day Initiative as ZDI-CAN-31642. (CVE-2026-74465)

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-2026-74465

Plugin Details

Severity: High

ID: 335890

File Name: unpatched_CVE_2026_74465.nasl

Version: 1.2

Type: Local

Agent: unix

Family: Misc.

Published: 8/15/2026

Updated: 8/16/2026

Supported Sensors: Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.3

Percentile: 53.55

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 6.1

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

CVSS Score Source: CVE-2026-74465

CVSS v3

Risk Factor: High

Base Score: 7.1

Temporal Score: 6.5

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

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

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:11.0, cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, p-cpe:/a:debian:debian_linux:linux

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

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 8/15/2026

Reference Information

CVE: CVE-2026-74465