CVE-2023-31436

HIGHNVD 7.87.8—

7.8

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.

CVSS v3: 7.8
EG Score: 7.8(medium)
EPSS: 43.2%
KEV: Not listed

Published

April 28, 2023

Last Modified

November 21, 2024

References (18)

cve@mitrehttp://packetstormsecurity.com/files/173087/Kernel-Live-Patch-Security-Notice-LSN-0095-1.html
cve@mitrehttp://packetstormsecurity.com/files/173757/Kernel-Live-Patch-Security-Notice-LSN-0096-1.html
cve@mitrehttp://packetstormsecurity.com/files/175963/Kernel-Live-Patch-Security-Notice-LSN-0099-1.html
cve@mitrehttps://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.2.13
cve@mitrehttps://github.com/torvalds/linux/commit/3037933448f60f9acb705997eae62013ecb81e0d
cve@mitrehttps://lists.debian.org/debian-lts-announce/2023/06/msg00008.html
cve@mitrehttps://security.netapp.com/advisory/ntap-20230609-0001/
cve@mitrehttps://www.debian.org/security/2023/dsa-5402
cve@mitrehttps://www.spinics.net/lists/stable-commits/msg294885.html
af854a3a-2127-422b-91ae-364da2661108http://packetstormsecurity.com/files/173087/Kernel-Live-Patch-Security-Notice-LSN-0095-1.html
af854a3a-2127-422b-91ae-364da2661108http://packetstormsecurity.com/files/173757/Kernel-Live-Patch-Security-Notice-LSN-0096-1.html
af854a3a-2127-422b-91ae-364da2661108http://packetstormsecurity.com/files/175963/Kernel-Live-Patch-Security-Notice-LSN-0099-1.html
af854a3a-2127-422b-91ae-364da2661108https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.2.13
af854a3a-2127-422b-91ae-364da2661108https://github.com/torvalds/linux/commit/3037933448f60f9acb705997eae62013ecb81e0d
af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2023/06/msg00008.html

Vendor Advisories for CVE-2023-31436(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(26)

Vendor / Ecosystem	Fixed in / Patch	Released	Source
ubuntu	linux-buildinfo-6.2.0-1007-gcp (6.2.0-1007.7) @ lunar	2026-05-25	ubuntu
ubuntu	linux-image-lowlatency (5.19.0.1025.21) @ kinetic	2026-05-25	ubuntu
ubuntu	linux-tools-aws-hwe (4.15.0.1157.140) @ xenial	2026-05-25	ubuntu
ubuntu	linux-tools-5.15.0-1031-intel-iotg (5.15.0-1031.36~20.04.1) @ focal	2026-05-25	ubuntu
ubuntu	linux-tools-iot (5.4.0.1017.15) @ focal	2026-05-25	ubuntu
ubuntu	lowlatency (5.15.0-25) @ jammy	2026-05-25	ubuntu
ubuntu	linux-image-unsigned-4.4.0-241-lowlatency (4.4.0-241.275) @ xenial	2026-05-25	ubuntu
ubuntu	lowlatency-4.4 (4.4.0-168) @ xenial	2026-05-25	ubuntu
ubuntu	linux-headers-5.4.0-1024-xilinx-zynqmp (5.4.0-1024.28) @ focal	2026-05-25	ubuntu
ubuntu	linux-virtual (3.13.0.194.204) @ trusty	2026-05-25	ubuntu
ubuntu	linux-image-aws (5.4.0.1103.81) @ bionic	2026-05-25	ubuntu
ubuntu	linux-headers-azure-fde (5.15.0.1039.46.16) @ jammy	2026-05-25	ubuntu
redhat	kernel-0:2.6.32-754.53.1.el6	2024-04-16	redhat
redhat	kernel-0:4.18.0-305.125.1.el8_4	2024-03-19	redhat
redhat	kpatch-patch	2024-03-19	redhat
redhat	kernel-rt-0:4.18.0-305.125.1.rt7.201.el8_4	2024-03-19	redhat
redhat	kernel-rt-0:4.18.0-193.128.1.rt13.179.el8_2	2024-03-12	redhat
redhat	kernel-0:4.18.0-193.128.1.el8_2	2024-03-12	redhat
redhat	kernel-0:4.18.0-477.43.1.el8_8	2024-01-30	redhat
redhat	kernel-0:4.18.0-372.87.1.el8_6	2024-01-25	redhat
redhat	kernel-0:3.10.0-1062.82.1.el7	2024-01-16	redhat
redhat	kernel-0:3.10.0-957.109.1.el7	2024-01-16	redhat
redhat	kernel-rt-0:3.10.0-1160.105.1.rt56.1256.el7	2023-11-21	redhat
redhat	kernel-0:3.10.0-1160.105.1.el7	2023-11-21	redhat
redhat	kernel-0:4.18.0-513.5.1.el8_9	2023-11-14	redhat
redhat	kernel-rt-0:4.18.0-513.5.1.rt7.307.el8_9	2023-11-14	redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-787Out-of-bounds Write

Additional Vendor Advisories

(23)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 13× in last 7d / 56× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

2026-06-21 14:55 UTCEPSS rescore
2026-06-21 14:55 UTCEPSS rescore
2026-06-21 01:58 UTCEPSS rescore
2026-06-21 01:58 UTCEPSS rescore
2026-06-19 19:24 UTCEPSS rescore
2026-06-19 19:24 UTCEPSS rescore
2026-06-18 17:51 UTCEPSS rescore
2026-06-18 17:51 UTCEPSS rescore
2026-06-17 17:51 UTCEPSS rescore
2026-06-17 17:51 UTCEPSS rescore
2026-06-16 17:51 UTCEPSS rescore
2026-06-16 17:51 UTCEPSS rescore
2026-06-15 17:47 UTCEPSS rescore
2026-06-14 23:16 UTCEPSS rescore
2026-06-13 22:59 UTCEPSS rescore
2026-06-13 22:59 UTCEPSS rescore
2026-06-12 23:10 UTCEPSS rescore
2026-06-11 13:59 UTCEPSS rescore
2026-06-10 22:17 UTCEPSS rescore
2026-06-10 13:21 UTCEPSS rescore
2026-06-10 13:21 UTCEPSS rescore
2026-06-10 09:17 UTCOSV refresh
2026-06-08 14:15 UTCEPSS rescore
2026-06-08 14:15 UTCEPSS rescore
2026-06-07 15:23 UTCEPSS rescore

Show 31 more

2026-06-07 15:23 UTCEPSS rescore
2026-06-06 13:46 UTCEPSS rescore
2026-06-06 13:46 UTCEPSS rescore
2026-06-05 22:46 UTCEPSS rescore
2026-06-05 22:46 UTCEPSS rescore
2026-06-05 06:09 UTCEPSS rescore
2026-06-05 06:09 UTCEPSS rescore
2026-06-04 13:11 UTCEPSS rescore
2026-06-04 13:11 UTCEPSS rescore
2026-06-02 20:12 UTCEPSS rescore
2026-06-02 20:12 UTCEPSS rescore
2026-06-02 20:12 UTCEPSS rescore
2026-06-01 13:51 UTCEPSS rescore
2026-05-31 22:29 UTCEPSS rescore
2026-05-31 22:29 UTCEPSS rescore
2026-05-31 22:29 UTCEPSS rescore
2026-05-31 00:15 UTCEPSS rescore
2026-05-31 00:15 UTCEPSS rescore
2026-05-29 13:43 UTCEPSS rescore
2026-05-28 13:43 UTCEPSS rescore
2026-05-28 13:43 UTCEPSS rescore
2026-05-27 13:39 UTCEPSS rescore
2026-05-27 13:39 UTCEPSS rescore
2026-05-26 13:43 UTCEPSS rescore
2026-05-26 13:43 UTCEPSS rescore
2026-05-26 07:18 UTCEPSS rescore
2026-05-26 07:18 UTCEPSS rescore
2026-05-26 07:17 UTCEPSS rescore
2026-05-25 02:15 UTCEG score recompute
2026-05-25 02:15 UTCVendor advisory
2026-05-25 02:14 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2023-31436?

CVE-2023-31436 is a high vulnerability published on April 28, 2023. qfqchangeclass in net/sched/schqfq.c in the Linux kernel before 6.2.13 allows an out-of-bounds write because lmax can exceed QFQMIN_LMAX.

When was CVE-2023-31436 disclosed?

CVE-2023-31436 was first published in the National Vulnerability Database on April 28, 2023, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2023-31436 actively exploited?

CVE-2023-31436 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 43.2% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2023-31436?

CVE-2023-31436 has a CVSS v3 base score of 7.8 (NVD).

How do I remediate CVE-2023-31436?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2023-31436, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2023-31436

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CVE-2023-31436

Published

Last Modified

References (18)

Vendor Advisories for CVE-2023-31436(2)

Patch Availability(26)

Weakness Classification(1)

Additional Vendor Advisories

Data Freshness Timeline

Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2023-31436?

Same vendor

Same CWE

CVE-2023-31436

📅 Published

🔄 Last Modified

🔗 References (18)

📣 Vendor Advisories for CVE-2023-31436(2)

Patch Availability(26)

Weakness Classification(1)

Additional Vendor Advisories

Data Freshness Timeline

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2023-31436?

🔗 Related CVEs(same vendor + same CWE)

Same vendor

Same CWE

Published

Last Modified

References (18)

Vendor Advisories for CVE-2023-31436(2)

Frequently asked(5)

Related CVEs(same vendor + same CWE)