Linux Distros Unpatched Vulnerability : CVE-2026-89508

medium Nessus Plugin ID 345439

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.

- RDMA/ucma: Lock the handler in ucma_set_ib_path() ucma_set_ib_path() calls ucma_event_handler() straight from the write() path, without the handler lock that keeps ctx->file stable while a uevent is queued. The handler re-reads ctx->file for every dereference: mutex_lock(&ctx->file->mut); /* file A */ list_add_tail(&uevent->list, &ctx->file->event_list); /* file B */ mutex_unlock(&ctx->file->mut); /* file B */ wake_up_interruptible(&ctx->file->poll_wait); /* file B */ A concurrent ucma_migrate_id() reassigns ctx->file while the SET_OPTION caller sleeps in mutex_lock(), so the list_add_tail() lands on file B's event_list while only file A's mutex is held, racing every other user of that list: BUG: KASAN: slab-use- after-free in __list_add_valid_or_report+0x1aa/0x1c0 Read of size 8 at addr ffff888153c6a418 by task poc_corr/486 Call Trace: __list_add_valid_or_report+0x1aa/0x1c0 ucma_event_handler+0x1be/0xc00 ucma_set_ib_path+0x45e/0x710 ucma_set_option+0x32e/0x590 ucma_write+0x1f9/0x330 Allocated by task 505:
ucma_write_cm_event+0x1a1/0x660 Freed by task 505: kfree+0x1da/0x4c0 ucma_get_event+0x5d5/0x7e0 The freed object is a ucma_event that another thread dequeued from file B's list under file B's mutex. File A's mut is left held on top of that, wedging its next writer in uninterruptible sleep. This path needs a bound and address-resolved cm_id, so it requires an RDMA device to be present. Take the handler lock around the call. (CVE-2026-89508)

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-2026-89508

Plugin Details

Severity: Medium

ID: 345439

File Name: unpatched_CVE_2026_89508.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 9/12/2026

Updated: 9/12/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.62

CVSS v2

Risk Factor: Medium

Base Score: 5.4

Temporal Score: 4.6

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

CVSS Score Source: CVE-2026-89508

CVSS v3

Risk Factor: Medium

Base Score: 5

Temporal Score: 4.6

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

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

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, cpe:/o:debian:debian_linux:14.0, 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: 9/11/2026

Reference Information

CVE: CVE-2026-89508