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Fencer Vulns
high 7.8

CVE-2023-31436 json

qfq_change_class in net/sched/sch_qfq.c in the Linux kernel before 6.2.13 allows an out-of-bounds write because lmax can exceed QFQ_MIN_LMA…

published 2023-04-28 3 y ago modified 2026-10-14 25 d ago also EUVD-2023-35744

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 48%
public exploits
0
none known

Summary

qfq_change_class in net/sched/sch_qfq.c in the Linux kernel before 6.2.13 allows an out-of-bounds write because lmax can exceed QFQ_MIN_LMAX.

Patch / fix

  • Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem V1.1
  • linux Debian 14, Debian 13, Debian 12 6.1.27-1

debian advisories DEBIAN-CVE-2023-31436

  • linux Ubuntu 18.04 LTS 4.15.0-212.223
  • linux Ubuntu 20.04 LTS 5.4.0-150.167
  • linux Ubuntu 22.04 LTS 5.15.0-73.80
  • linux-aws Ubuntu 18.04 LTS 4.15.0-1157.170
  • linux-aws Ubuntu 20.04 LTS 5.4.0-1103.111
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1037.41
  • linux-gcp Ubuntu 20.04 LTS 5.4.0-1106.115
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1035.43

ubuntu advisories UBUNTU-CVE-2023-31436

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • perf rhev hypervisor 4.4, RHEL 8.6 EUS 4.18.0-372.87.1.el8_6
  • kernel RHEL 8 4.18.0-513.5.1.el8_9
  • perf RHEL 8 4.18.0-513.5.1.el8_9
  • bpftool RHEL 8 4.18.0-513.5.1.el8_9
  • kernel-core RHEL 8 4.18.0-513.5.1.el8_9
  • kernel-tools RHEL 8 4.18.0-513.5.1.el8_9
  • python3-perf RHEL 8 4.18.0-513.5.1.el8_9
  • kernel-modules RHEL 8 4.18.0-513.5.1.el8_9

red hat advisories RHSA-2024:1382RHSA-2024:1367RHSA-2024:0412RHSA-2023:7077RHSA-2023:6901RHSA-2024:0575

  • dtb-aarch64 openSUSE Leap 15.5 5.14.21-150500.55.7.1
  • kernel-64kb SLE Module for Basesystem 15 SP5, openSUSE Leap 15.5 5.14.21-150500.55.7.1
  • kernel-syms SLE Module for Development Tools 15 SP5, openSUSE Leap 15.5 5.14.21-150500.55.7.1
  • kernel-obs-qa openSUSE Leap 15.5 5.14.21-150500.55.7.1
  • kernel-source SLE Module for Development Tools 15 SP5, SLE Module for Basesystem 15 SP5, openSUSE Leap 15.5 5.14.21-150500.55.7.1
  • kernel-default SLE Workstation Extension 15 SP5, SLE Module for Legacy 15 SP5, SLE Module for Basesystem 15 SP5 +3 more 5.14.21-150500.55.7.1
  • kernel-kvmsmall openSUSE Leap 15.5 5.14.21-150500.55.7.1
  • kernel-zfcpdump SLE Module for Basesystem 15 SP5, openSUSE Leap 15.5 5.14.21-150500.55.7.1

suse advisories SUSE-SU-2023:2871-1SUSE-SU-2023:2809-1SUSE-SU-2023:2805-1SUSE-SU-2023:2782-1SUSE-SU-2023:2755-1SUSE-SU-2023:2743-1

  • kernel AlmaLinux 8 4.18.0-513.5.1.el8_9
  • perf AlmaLinux 8 4.18.0-513.5.1.el8_9
  • bpftool AlmaLinux 8 4.18.0-513.5.1.el8_9
  • kernel-core AlmaLinux 8 4.18.0-513.5.1.el8_9
  • kernel-tools AlmaLinux 8 4.18.0-513.5.1.el8_9
  • python3-perf AlmaLinux 8 4.18.0-513.5.1.el8_9
  • kernel-modules AlmaLinux 8 4.18.0-513.5.1.el8_9
  • kernel-zfcpdump AlmaLinux 8 4.18.0-513.5.1.el8_9

almalinux advisories ALSA-2023:7077

  • kernel CBL-Mariner 2.0 5.15.111.1-1
  • hyperv-daemons CBL-Mariner 2.0 5.15.111.1-1

azure linux advisories AZL-26391AZL-26668

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-31436 updated cvss 7.0

kernel: out-of-bounds write in qfq_change_class function

  • Red Hat Enterprise Linux 7 kernel-rt, kernel-rt-kvm, kernel-rt-trace, kernel-rt-debug-kvm, kernel-rt-trace-kvm
    affected: workaround, no fix available
  • Red Hat CodeReady Linux Builder (v. 8) kernel-debuginfo-common-x86_64 4.18.0-513.5.1.el8_9, kernel-debuginfo-common-aarch64 4.18.0-513.5.1.el8_9, kernel-debuginfo-common-ppc64le 4.18.0-513.5.1.el8_9
    fixed: vendor fix RHSA-2023:7077
  • Red Hat CodeReady Linux Builder EUS (v.8.6) kernel-debuginfo-common-x86_64 4.18.0-372.87.1.el8_6, kernel-debuginfo-common-aarch64 4.18.0-372.87.1.el8_6, kernel-debuginfo-common-ppc64le 4.18.0-372.87.1.el8_6
    fixed: vendor fix RHSA-2024:0412
  • Red Hat CodeReady Linux Builder EUS (v.8.8) kernel-debuginfo-common-x86_64 4.18.0-477.43.1.el8_8, kernel-debuginfo-common-aarch64 4.18.0-477.43.1.el8_8, kernel-debuginfo-common-ppc64le 4.18.0-477.43.1.el8_8
    fixed: vendor fix RHSA-2024:0575
  • Red Hat Enterprise Linux BaseOS (v. 8) perf 4.18.0-513.5.1.el8_9, kernel 4.18.0-513.5.1.el8_9, bpftool 4.18.0-513.5.1.el8_9, kernel-core 4.18.0-513.5.1.el8_9, kernel-tools 4.18.0-513.5.1.el8_9, python3-perf 4.18.0-513.5.1.el8_9, +15 more
    fixed: vendor fix RHSA-2023:7077
  • Red Hat Enterprise Linux BaseOS AUS (v. 8.2) perf 4.18.0-193.128.1.el8_2, kernel 4.18.0-193.128.1.el8_2, bpftool 4.18.0-193.128.1.el8_2, kernel-core 4.18.0-193.128.1.el8_2, kernel-tools 4.18.0-193.128.1.el8_2, python3-perf 4.18.0-193.128.1.el8_2, +8 more
    fixed: vendor fix RHSA-2024:1268
  • Red Hat Enterprise Linux BaseOS AUS (v.8.4) perf 4.18.0-305.125.1.el8_4, kernel 4.18.0-305.125.1.el8_4, bpftool 4.18.0-305.125.1.el8_4, kernel-core 4.18.0-305.125.1.el8_4, kernel-tools 4.18.0-305.125.1.el8_4, python3-perf 4.18.0-305.125.1.el8_4, +8 more
    fixed: vendor fix RHSA-2024:1367
  • Red Hat Enterprise Linux BaseOS E4S (v. 8.2) perf 4.18.0-193.128.1.el8_2, kernel 4.18.0-193.128.1.el8_2, bpftool 4.18.0-193.128.1.el8_2, kernel-core 4.18.0-193.128.1.el8_2, kernel-tools 4.18.0-193.128.1.el8_2, python3-perf 4.18.0-193.128.1.el8_2, +13 more
    fixed: vendor fix RHSA-2024:1268
show 21 more
  • Red Hat Enterprise Linux BaseOS E4S (v.8.4) perf 4.18.0-305.125.1.el8_4, kernel 4.18.0-305.125.1.el8_4, bpftool 4.18.0-305.125.1.el8_4, kernel-core 4.18.0-305.125.1.el8_4, kernel-tools 4.18.0-305.125.1.el8_4, python3-perf 4.18.0-305.125.1.el8_4, +13 more
    fixed: vendor fix RHSA-2024:1367
  • Red Hat Enterprise Linux BaseOS EUS (v.8.6) perf 4.18.0-372.87.1.el8_6, kernel 4.18.0-372.87.1.el8_6, bpftool 4.18.0-372.87.1.el8_6, kernel-core 4.18.0-372.87.1.el8_6, kernel-tools 4.18.0-372.87.1.el8_6, python3-perf 4.18.0-372.87.1.el8_6, +19 more
    fixed: vendor fix RHSA-2024:0412
  • Red Hat Enterprise Linux BaseOS EUS (v.8.8) perf 4.18.0-477.43.1.el8_8, kernel 4.18.0-477.43.1.el8_8, bpftool 4.18.0-477.43.1.el8_8, kernel-core 4.18.0-477.43.1.el8_8, kernel-tools 4.18.0-477.43.1.el8_8, python3-perf 4.18.0-477.43.1.el8_8, +18 more
    fixed: vendor fix RHSA-2024:0575
  • Red Hat Enterprise Linux BaseOS TUS (v. 8.2) perf 4.18.0-193.128.1.el8_2, kernel 4.18.0-193.128.1.el8_2, bpftool 4.18.0-193.128.1.el8_2, kernel-core 4.18.0-193.128.1.el8_2, kernel-tools 4.18.0-193.128.1.el8_2, python3-perf 4.18.0-193.128.1.el8_2, +8 more
    fixed: vendor fix RHSA-2024:1268
  • Red Hat Enterprise Linux BaseOS TUS (v.8.4) perf 4.18.0-305.125.1.el8_4, kernel 4.18.0-305.125.1.el8_4, bpftool 4.18.0-305.125.1.el8_4, kernel-core 4.18.0-305.125.1.el8_4, kernel-tools 4.18.0-305.125.1.el8_4, python3-perf 4.18.0-305.125.1.el8_4, +8 more
    fixed: vendor fix RHSA-2024:1367
  • Red Hat Enterprise Linux Client (v. 7) perf 3.10.0-1160.105.1.el7, kernel 3.10.0-1160.105.1.el7, bpftool 3.10.0-1160.105.1.el7, python-perf 3.10.0-1160.105.1.el7, kernel-tools 3.10.0-1160.105.1.el7, kernel-tools-libs 3.10.0-1160.105.1.el7, +2 more Red Hat Enterprise Linux Client Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1160.105.1.el7 Red Hat Enterprise Linux ComputeNode Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1160.105.1.el7
    fixed: vendor fix RHSA-2023:7423
  • Red Hat Enterprise Linux NFV TUS (v.8.4) kernel-rt 4.18.0-305.125.1.rt7.201.el8_4, kernel-rt-kvm 4.18.0-305.125.1.rt7.201.el8_4, kernel-rt-core 4.18.0-305.125.1.rt7.201.el8_4, kernel-rt-modules 4.18.0-305.125.1.rt7.201.el8_4, kernel-rt-debug-kvm 4.18.0-305.125.1.rt7.201.el8_4, kernel-rt-debug-core 4.18.0-305.125.1.rt7.201.el8_4, +4 more
    fixed: vendor fix RHSA-2024:1382
  • Red Hat Enterprise Linux Real Time (v. 8) kernel-rt 4.18.0-513.5.1.rt7.307.el8_9, kernel-rt-core 4.18.0-513.5.1.rt7.307.el8_9, kernel-rt-modules 4.18.0-513.5.1.rt7.307.el8_9, kernel-rt-debug-core 4.18.0-513.5.1.rt7.307.el8_9, kernel-rt-debug-modules 4.18.0-513.5.1.rt7.307.el8_9, kernel-rt-modules-extra 4.18.0-513.5.1.rt7.307.el8_9, +2 more Red Hat Enterprise Linux Real Time for NFV (v. 8) kernel-rt 4.18.0-513.5.1.rt7.307.el8_9, kernel-rt-kvm 4.18.0-513.5.1.rt7.307.el8_9, kernel-rt-core 4.18.0-513.5.1.rt7.307.el8_9, kernel-rt-modules 4.18.0-513.5.1.rt7.307.el8_9, kernel-rt-debug-kvm 4.18.0-513.5.1.rt7.307.el8_9, kernel-rt-debug-core 4.18.0-513.5.1.rt7.307.el8_9, +4 more
    fixed: vendor fix RHSA-2023:6901
  • Red Hat Enterprise Linux Real Time for NFV TUS (v. 8.2) kernel-rt 4.18.0-193.128.1.rt13.179.el8_2, kernel-rt-kvm 4.18.0-193.128.1.rt13.179.el8_2, kernel-rt-core 4.18.0-193.128.1.rt13.179.el8_2, kernel-rt-modules 4.18.0-193.128.1.rt13.179.el8_2, kernel-rt-debug-kvm 4.18.0-193.128.1.rt13.179.el8_2, kernel-rt-debug-core 4.18.0-193.128.1.rt13.179.el8_2, +4 more Red Hat Enterprise Linux Real Time TUS (v. 8.2) kernel-rt 4.18.0-193.128.1.rt13.179.el8_2, kernel-rt-core 4.18.0-193.128.1.rt13.179.el8_2, kernel-rt-modules 4.18.0-193.128.1.rt13.179.el8_2, kernel-rt-debug-core 4.18.0-193.128.1.rt13.179.el8_2, kernel-rt-debug-modules 4.18.0-193.128.1.rt13.179.el8_2, kernel-rt-modules-extra 4.18.0-193.128.1.rt13.179.el8_2, +2 more
    fixed: vendor fix RHSA-2024:1269
  • Red Hat Enterprise Linux RT TUS (v.8.4) kernel-rt 4.18.0-305.125.1.rt7.201.el8_4, kernel-rt-core 4.18.0-305.125.1.rt7.201.el8_4, kernel-rt-modules 4.18.0-305.125.1.rt7.201.el8_4, kernel-rt-debug-core 4.18.0-305.125.1.rt7.201.el8_4, kernel-rt-debug-modules 4.18.0-305.125.1.rt7.201.el8_4, kernel-rt-modules-extra 4.18.0-305.125.1.rt7.201.el8_4, +2 more
    fixed: vendor fix RHSA-2024:1382
  • Red Hat Enterprise Linux Server (v. 6 ELS) perf 2.6.32-754.53.1.el6, kernel 2.6.32-754.53.1.el6, kernel-kdump 2.6.32-754.53.1.el6, kernel-firmware 2.6.32-754.53.1.el6, kernel-abi-whitelists 2.6.32-754.53.1.el6, kernel-debuginfo-common-i686 2.6.32-754.53.1.el6, +2 more
    fixed: vendor fix RHSA-2024:1831
  • Red Hat Enterprise Linux Server (v. 7) perf 3.10.0-1160.105.1.el7, kernel 3.10.0-1160.105.1.el7, bpftool 3.10.0-1160.105.1.el7, python-perf 3.10.0-1160.105.1.el7, kernel-kdump 3.10.0-1160.105.1.el7, kernel-tools 3.10.0-1160.105.1.el7, +11 more
    fixed: vendor fix RHSA-2023:7423
  • Red Hat Enterprise Linux Server AUS (v. 7.6) perf 3.10.0-957.109.1.el7, kernel 3.10.0-957.109.1.el7, bpftool 3.10.0-957.109.1.el7, python-perf 3.10.0-957.109.1.el7, kernel-tools 3.10.0-957.109.1.el7, kernel-tools-libs 3.10.0-957.109.1.el7, +2 more
    fixed: vendor fix RHSA-2024:0261
  • Red Hat Enterprise Linux Server AUS (v. 7.7) perf 3.10.0-1062.82.1.el7, kernel 3.10.0-1062.82.1.el7, bpftool 3.10.0-1062.82.1.el7, python-perf 3.10.0-1062.82.1.el7, kernel-tools 3.10.0-1062.82.1.el7, kernel-tools-libs 3.10.0-1062.82.1.el7, +2 more
    fixed: vendor fix RHSA-2024:0262
  • Red Hat Enterprise Linux Server Optional (v. 6 ELS) python-perf 2.6.32-754.53.1.el6, kernel-debuginfo-common-i686 2.6.32-754.53.1.el6, kernel-debuginfo-common-s390x 2.6.32-754.53.1.el6, kernel-debuginfo-common-x86_64 2.6.32-754.53.1.el6
    fixed: vendor fix RHSA-2024:1831
  • Red Hat Enterprise Linux Server Optional (v. 7) kernel-debuginfo-common-ppc64 3.10.0-1160.105.1.el7, kernel-debuginfo-common-x86_64 3.10.0-1160.105.1.el7, kernel-debuginfo-common-ppc64le 3.10.0-1160.105.1.el7
    fixed: vendor fix RHSA-2023:7423
  • Red Hat Enterprise Linux Server Optional AUS (v. 7.6) kernel-debuginfo-common-x86_64 3.10.0-957.109.1.el7
    fixed: vendor fix RHSA-2024:0261
  • Red Hat Enterprise Linux Server Optional AUS (v. 7.7) kernel-debuginfo-common-x86_64 3.10.0-1062.82.1.el7
    fixed: vendor fix RHSA-2024:0262
  • Red Hat Enterprise Linux Workstation (v. 7) perf 3.10.0-1160.105.1.el7, kernel 3.10.0-1160.105.1.el7, bpftool 3.10.0-1160.105.1.el7, python-perf 3.10.0-1160.105.1.el7, kernel-tools 3.10.0-1160.105.1.el7, kernel-tools-libs 3.10.0-1160.105.1.el7, +2 more Red Hat Enterprise Linux Workstation Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1160.105.1.el7
    fixed: vendor fix RHSA-2023:7423
  • Red Hat Virtualization 4 Hypervisor for RHEL 8 perf 4.18.0-372.87.1.el8_6, kernel-debuginfo-common-x86_64 4.18.0-372.87.1.el8_6
    fixed: vendor fix RHSA-2024:0412
  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-23-166-11 updated cvss 7.8

Siemens SIMATIC S7-1500 TM MFP Linux Kernel

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-24-046-11 updated cvss 7.8

Siemens SCALANCE XCM-/XRM-300

  • Siemens SCALANCE XCH328 (6GK5328-4TS01-2EC2) <V2.4 Siemens SCALANCE XCM324 (6GK5324-8TS01-2AC2) <V2.4 Siemens SCALANCE XCM328 (6GK5328-4TS01-2AC2) <V2.4 Siemens SCALANCE XCM332 (6GK5332-0GA01-2AC2) <V2.4 Siemens SCALANCE XRH334 (24 V DC, 8xFO, CC) (6GK5334-2TS01-2ER3) <V2.4 Siemens SCALANCE XRM334 (2x230 V AC, 8xFO) (6GK5334-2TS01-4AR3) <V2.4
    +5 more products
    Siemens SCALANCE XRM334 (2x230 V AC, 12xFO) (6GK5334-3TS01-4AR3) <V2.4 Siemens SCALANCE XRM334 (24 V DC, 8xFO) (6GK5334-2TS01-2AR3) <V2.4 Siemens SCALANCE XRM334 (24 V DC, 12xFO) (6GK5334-3TS01-2AR3) <V2.4 Siemens SCALANCE XRM334 (230 V AC, 8xFO) (6GK5334-2TS01-3AR3) <V2.4 Siemens SCALANCE XRM334 (230 V AC, 12xFO) (6GK5334-3TS01-3AR3) <V2.4
    affected: fixed in V2.4 support.industry.siemens.com

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
2 y ago

Exploit prediction

0.60% chance of exploitation in the next 30 days, higher than 48% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem

Classification

Weakness
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.