Linux Distros Unpatched Vulnerability : CVE-2026-98897

critical Nessus Plugin ID 371526

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.

- ksmbd: don't hold ci->m_lock while waiting for a lease break ack When a cifs.ko client caches a read- handle (RH) lease via deferred close and a conflicting open arrives, ksmbd breaks the lease and waits for the acknowledgment in wait_for_break_ack() for up to OPLOCK_WAIT_TIME (35s).
__smb_break_all_levII_oplock() runs that wait while holding ci->m_lock for read. cifs.ko reacts to a handle-lease break by closing the deferred handle rather than sending a lease break acknowledgment. That close path (close_id_del_oplock() -> opinfo_del()) takes ci->m_lock for write and is exactly what would wake the waiter, but it blocks on the read lock held by the waiting thread. The break is then resolved only by the 35s timeout, so xfstests generic/001 takes ~78s with leases enabled versus ~4s with oplocks only. Collect the target opinfos (each pinned with a reference) while holding ci->m_lock, then break them after releasing it, matching how smb_grant_oplock() already breaks a conflicting lease using only a reference. The reference keeps the opinfo (and its conn and lease) alive across the unlocked window, and a close racing the break is handled by the existing OPLOCK_CLOSING state check. Apply the same fix to the parent lease break paths. (CVE-2026-98897)

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-2026-98897

Plugin Details

Severity: Critical

ID: 371526

File Name: unpatched_CVE_2026_98897.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 10/23/2026

Updated: 10/23/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.6

Percentile: 98.19

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-2026-98897

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: 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: 10/23/2026

Reference Information

CVE: CVE-2026-98897