Linux Distros Unpatched Vulnerability : CVE-2026-23286

high Nessus Plugin ID 303657

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.

- atm: lec: fix null-ptr-deref in lec_arp_clear_vccs syzkaller reported a null-ptr-deref in lec_arp_clear_vccs(). This issue can be easily reproduced using the syzkaller reproducer. In the ATM LANE (LAN Emulation) module, the same atm_vcc can be shared by multiple lec_arp_table entries (e.g., via entry->vcc or entry->recv_vcc). When the underlying VCC is closed, lec_vcc_close() iterates over all ARP entries and calls lec_arp_clear_vccs() for each matched entry. For example, when lec_vcc_close() iterates through the hlists in priv->lec_arp_empty_ones or other ARP tables: 1. In the first iteration, for the first matched ARP entry sharing the VCC, lec_arp_clear_vccs() frees the associated vpriv (which is vcc->user_back) and sets vcc->user_back to NULL. 2. In the second iteration, for the next matched ARP entry sharing the same VCC, lec_arp_clear_vccs() is called again. It obtains a NULL vpriv from vcc->user_back (via LEC_VCC_PRIV(vcc)) and then attempts to dereference it via `vcc->pop = vpriv->old_pop`, leading to a null-ptr-deref crash. Fix this by adding a null check for vpriv before dereferencing it. If vpriv is already NULL, it means the VCC has been cleared by a previous call, so we can safely skip the cleanup and just clear the entry's vcc/recv_vcc pointers. The entire cleanup block (including vcc_release_async()) is placed inside the vpriv guard because a NULL vpriv indicates the VCC has already been fully released by a prior iteration repeating the teardown would redundantly set flags and trigger callbacks on an already-closing socket. The Fixes tag points to the initial commit because the entry->vcc path has been vulnerable since the original code. The entry->recv_vcc path was later added by commit 8d9f73c0ad2f (atm: fix a memory leak of vcc->user_back) with the same pattern, and both paths are fixed here. (CVE-2026-23286)

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://access.redhat.com/security/cve/cve-2026-23286

https://security-tracker.debian.org/tracker/CVE-2026-23286

Plugin Details

Severity: High

ID: 303657

File Name: unpatched_CVE_2026_23286.nasl

Version: 1.1

Type: local

Agent: unix

Family: Misc.

Published: 3/25/2026

Updated: 3/25/2026

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

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 4.9

Temporal Score: 4.2

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

CVSS Score Source: CVE-2026-23286

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, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-rt-core, p-cpe:/a:centos:centos:kernel-rt-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-devel, p-cpe:/a:centos:centos:kernel-rt-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-core, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-doc, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-devel, p-cpe:/a:centos:centos:kernel-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-64k-modules-extra, p-cpe:/a:centos:centos:kernel-kdump-devel, p-cpe:/a:centos:centos:kernel-devel, p-cpe:/a:centos:centos:kernel-rt-64k-modules, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-modules, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-kvm, p-cpe:/a:centos:centos:kernel-64k-debug, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules, p-cpe:/a:centos:centos:kernel-rt-64k-modules-internal, cpe:/o:redhat:enterprise_linux:9, p-cpe:/a:centos:centos:libperf, p-cpe:/a:redhat:enterprise_linux:kernel-debug-modules-extra, p-cpe:/a:centos:centos:kernel-rt-core, p-cpe:/a:centos:centos:kernel-rt-doc, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug, p-cpe:/a:redhat:enterprise_linux:kernel, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-modules-extra, p-cpe:/a:centos:centos:kernel-kdump, p-cpe:/a:centos:centos:kernel-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-64k-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-modules, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-modules-extra, p-cpe:/a:centos:centos:kernel-rt-64k-debug-kvm, p-cpe:/a:redhat:enterprise_linux:libperf-devel, p-cpe:/a:centos:centos:kernel-64k-modules-extra, p-cpe:/a:centos:centos:python-perf, p-cpe:/a:redhat:enterprise_linux:kernel-modules, p-cpe:/a:centos:centos:kernel-64k-modules-core, p-cpe:/a:centos:centos:kernel-64k-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules-extra, p-cpe:/a:centos:centos:kernel-64k-modules, p-cpe:/a:centos:centos:kernel-rt-devel, p-cpe:/a:centos:centos:kernel-debug-uki-virt-addons, p-cpe:/a:centos:centos:kernel-rt-modules-extra, p-cpe:/a:centos:centos:python3-perf, p-cpe:/a:redhat:enterprise_linux:kernel-rt-selftests-internal, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-modules-partner, p-cpe:/a:centos:centos:kernel-bootwrapper, p-cpe:/a:centos:centos:kernel-64k-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-rt-devel-matched, cpe:/o:redhat:enterprise_linux:7, p-cpe:/a:centos:centos:kernel-zfcpdump, p-cpe:/a:redhat:enterprise_linux:kernel-rt-trace-devel, p-cpe:/a:redhat:enterprise_linux:kernel-bootwrapper, p-cpe:/a:redhat:enterprise_linux:kernel-debug-modules-internal, p-cpe:/a:redhat:enterprise_linux:python-perf, p-cpe:/a:redhat:enterprise_linux:kernel-64k-core, p-cpe:/a:redhat:enterprise_linux:kernel-abi-whitelists, p-cpe:/a:centos:centos:kernel-64k-debug-modules-internal, p-cpe:/a:centos:centos:kernel-64k-debug-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-modules-internal, p-cpe:/a:centos:centos:kernel-rt-64k-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs-devel, p-cpe:/a:centos:centos:kernel-rt-selftests-internal, p-cpe:/a:centos:centos:kernel-zfcpdump-devel-matched, p-cpe:/a:centos:centos:kernel-zfcpdump-modules-partner, p-cpe:/a:centos:centos:kernel-rt-trace-kvm, p-cpe:/a:redhat:enterprise_linux:kernel-core, p-cpe:/a:redhat:enterprise_linux:kernel-cross-headers, p-cpe:/a:redhat:enterprise_linux:kernel-rt-doc, p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs, p-cpe:/a:centos:centos:kernel-debug-devel-matched, p-cpe:/a:centos:centos:kernel-rt-64k-debug-modules-extra, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:perf, p-cpe:/a:centos:centos:kernel-64k-devel, p-cpe:/a:redhat:enterprise_linux:kernel-abi-stablelists, p-cpe:/a:centos:centos:kernel-headers, p-cpe:/a:centos:centos:kernel-rt-modules, p-cpe:/a:centos:centos:kernel-64k-debug-devel-matched, p-cpe:/a:centos:centos:kernel-debug-core, p-cpe:/a:centos:centos:kernel-tools-libs-devel, p-cpe:/a:centos:centos:kernel-64k-core, p-cpe:/a:centos:centos:kernel-debug-modules-internal, p-cpe:/a:redhat:enterprise_linux:bpftool, p-cpe:/a:redhat:enterprise_linux:kernel-64k-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-rt-kvm, p-cpe:/a:centos:centos:kernel-zfcpdump-modules-core, p-cpe:/a:centos:centos:kernel-rt-debug-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-modules-internal, p-cpe:/a:centos:centos:kernel-rt-64k-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-devel, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-devel-matched, p-cpe:/a:centos:centos:kernel-rt-64k-debug-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-devel, p-cpe:/a:centos:centos:kernel-modules-extra, p-cpe:/a:centos:centos:kernel-cross-headers, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-modules-extra, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-kvm, p-cpe:/a:redhat:enterprise_linux:kernel-uki-virt-addons, p-cpe:/a:centos:centos:kernel-rt-kvm, p-cpe:/a:centos:centos:kernel-rt-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules-partner, p-cpe:/a:debian:debian_linux:linux, p-cpe:/a:centos:centos:kernel-rt, p-cpe:/a:centos:centos:kernel-rt-modules-internal, p-cpe:/a:centos:centos:kernel-tools, p-cpe:/a:centos:centos:kernel-rt-debug-modules-extra, p-cpe:/a:centos:centos:kernel-debug-uki-virt, p-cpe:/a:redhat:enterprise_linux:kernel-kdump, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules-extra, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules-core, p-cpe:/a:centos:centos:kernel-rt-trace, p-cpe:/a:centos:centos:kernel-rt-modules-partner, p-cpe:/a:centos:centos:kernel-rt-64k-debug-modules, p-cpe:/a:centos:centos:kernel-rt-debug, p-cpe:/a:redhat:enterprise_linux:kernel-64k-devel-matched, p-cpe:/a:centos:centos:kernel-abi-stablelists, p-cpe:/a:redhat:enterprise_linux:kernel-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules, p-cpe:/a:redhat:enterprise_linux:kernel-debug-core, p-cpe:/a:centos:centos:kernel-rt-64k-modules-partner, p-cpe:/a:centos:centos:kernel-64k-debug-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-modules-internal, p-cpe:/a:centos:centos:kernel-rt-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-trace-kvm, p-cpe:/a:centos:centos:kernel-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-modules, p-cpe:/a:redhat:enterprise_linux:kernel-modules-core, p-cpe:/a:centos:centos:kernel-core, p-cpe:/a:centos:centos:kernel-rt-64k-kvm, p-cpe:/a:redhat:enterprise_linux:kernel-kdump-devel, p-cpe:/a:centos:centos:kernel-debug-modules-partner, p-cpe:/a:centos:centos:kernel-debug-modules-extra, p-cpe:/a:redhat:enterprise_linux:kernel-debug, p-cpe:/a:centos:centos:kernel-rt-debug-core, p-cpe:/a:centos:centos:kernel-devel-matched, p-cpe:/a:centos:centos:kernel-rt-64k-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-64k-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-modules-partner, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-devel, p-cpe:/a:centos:centos:kernel-rt-debug-modules, p-cpe:/a:centos:centos:kernel-rt-64k, p-cpe:/a:centos:centos:kernel, p-cpe:/a:centos:centos:kernel-debug-modules-core, p-cpe:/a:centos:centos:kernel-rt-trace-devel, p-cpe:/a:centos:centos:kernel-rt-64k-debug-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug, p-cpe:/a:centos:centos:kernel-uki-virt-addons, p-cpe:/a:centos:centos:kernel-uki-virt, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-kvm, p-cpe:/a:centos:centos:kernel-rt-64k-debug-core, p-cpe:/a:centos:centos:kernel-doc, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules-internal, p-cpe:/a:centos:centos:kernel-rt-debug-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-tools, p-cpe:/a:centos:centos:kernel-rt-64k-modules-core, p-cpe:/a:centos:centos:kernel-zfcpdump-core, p-cpe:/a:centos:centos:kernel-64k-debug-modules-extra, p-cpe:/a:centos:centos:kernel-zfcpdump-devel, p-cpe:/a:centos:centos:kernel-tools-libs, p-cpe:/a:redhat:enterprise_linux:kernel-debug-uki-virt-addons, p-cpe:/a:centos:centos:kernel-abi-whitelists, p-cpe:/a:redhat:enterprise_linux:kernel-64k, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug, p-cpe:/a:redhat:enterprise_linux:kernel-64k-modules-core, p-cpe:/a:redhat:enterprise_linux:rv, p-cpe:/a:redhat:enterprise_linux:kernel-rt-trace, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-modules-core, p-cpe:/a:redhat:enterprise_linux:kernel-uki-virt, cpe:/o:redhat:enterprise_linux:8, cpe:/o:debian:debian_linux:13.0, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-core, p-cpe:/a:centos:centos:libperf-devel, p-cpe:/a:centos:centos:kernel-64k, p-cpe:/a:redhat:enterprise_linux:kernel-headers, p-cpe:/a:redhat:enterprise_linux:libperf, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-modules-core, p-cpe:/a:centos:centos:kernel-64k-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-debug-modules, cpe:/o:centos:centos:7, p-cpe:/a:redhat:enterprise_linux:python3-perf, p-cpe:/a:redhat:enterprise_linux:kernel-selftests-internal, p-cpe:/a:centos:centos:kernel-ipaclones-internal, p-cpe:/a:centos:centos:kernel-debug, p-cpe:/a:redhat:enterprise_linux:kernel-debug-devel-matched, p-cpe:/a:centos:centos:rtla, p-cpe:/a:redhat:enterprise_linux:rtla, p-cpe:/a:redhat:enterprise_linux:kernel-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules-internal, p-cpe:/a:centos:centos:kernel-rt-64k-modules-extra, p-cpe:/a:centos:centos:kernel-rt-64k-devel-matched, p-cpe:/a:redhat:enterprise_linux:kernel-debug-modules-core, p-cpe:/a:centos:centos:kernel-64k-debug-modules, p-cpe:/a:centos:centos:kernel-zfcpdump-modules-extra, p-cpe:/a:centos:centos:kernel-selftests-internal, p-cpe:/a:centos:centos:kernel-modules-internal, p-cpe:/a:centos:centos:kernel-debug-modules, p-cpe:/a:redhat:enterprise_linux:kernel-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-ipaclones-internal, p-cpe:/a:centos:centos:kernel-rt-64k-debug, p-cpe:/a:centos:centos:kernel-rt-64k-debug-devel, p-cpe:/a:centos:centos:rv, p-cpe:/a:redhat:enterprise_linux:kernel-rt, p-cpe:/a:centos:centos:kernel-rt-64k-debug-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-64k-modules, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump-modules-partner, cpe:/o:debian:debian_linux:12.0, p-cpe:/a:redhat:enterprise_linux:kernel-debug-uki-virt, p-cpe:/a:centos:centos:kernel-zfcpdump-modules, p-cpe:/a:redhat:enterprise_linux:kernel-zfcpdump, p-cpe:/a:centos:centos:kernel-64k-debug-devel, p-cpe:/a:centos:centos:perf, p-cpe:/a:centos:centos:kernel-rt-debug-kvm, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-debug-core, p-cpe:/a:centos:centos:kernel-modules, cpe:/o:centos:centos:8, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-modules-extra, p-cpe:/a:centos:centos:kernel-zfcpdump-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k-modules-partner, p-cpe:/a:centos:centos:bpftool, p-cpe:/a:redhat:enterprise_linux:kernel-rt-64k, p-cpe:/a:centos:centos:kernel-rt-debug-modules-internal, p-cpe:/a:redhat:enterprise_linux:kernel-modules-extra, p-cpe:/a:redhat:enterprise_linux:kernel-64k-debug-modules, p-cpe:/a:centos:centos:kernel-64k-devel-matched

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: 3/25/2026

Reference Information

CVE: CVE-2026-23286