BlackTreeIndependent security intelligence

Full vulnerability report · 2025

CVE-2023-53576High confidence

null_blk: Always check queue mode setting from configfs

Linux · Linux

5.5MediumCVSS 3.1

Recommended action

Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available

Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

9 package states

Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Ubuntu release	Source package	Vendor state	Fixed version	Evidence
Ubuntu 24.04 LTSnoble · standard archive	`linux-azure-6.11`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-gcp-6.11`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-hwe-6.11`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-intel`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-lowlatency-hwe-6.11`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-oem-6.11`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-raspi-realtime`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-realtime`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-riscv`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical record ↗Source updated 9 Sept 2026

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current

ENISA EUVD identifier

EUVD-2025-32317

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state: Present in the current official mapping
Known exploitation: Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score: Not supplied in the stored EUVD record
Advisory evidence: No linked advisory details stored yet

Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available

What, why and how

In the Linux kernel, the following vulnerability has been resolved: null_blk: Always check queue mode setting from configfs Make sure to check device queue mode in the null_validate_conf() and return error for NULL_Q_RQ as we don't allow legacy I/O path, without this patch we get OOPs when queue mode is set to 1 from configfs, following are repro steps :- modprobe null_blk nr_devices=0 mkdir config/nullb/nullb0 echo 1 > config/nullb/nullb0/memory_backed echo 4096 > config/nullb/nullb0/blocksize echo 20480 > config/nullb/nullb0/size echo 1 > config/nullb/nullb0/queue_mode echo 1 > config/nullb/nullb0/power Entering kdb (current=0xffff88810acdd080, pid 2372) on processor 42 Oops: (null) due to oops @ 0xffffffffc041c329 CPU: 42 PID: 2372 Comm: sh Tainted: G O N 6.3.0-rc5lblk+ #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 RIP: 0010:null_add_dev.part.0+0xd9/0x720 [null_blk] Code: 01 00 00 85 d2 0f 85 a1 03 00 00 48 83 bb 08 01 00 00 00 0f 85 f7 03 00 00 80 bb 62 01 00 00 00 48 8b 75 20 0f 85 6d 02 00 00 <48> 89 6e 60 48 8b 75 20 bf 06 00 00 00 e8 f5 37 2c c1 48 8b 75 20 RSP: 0018:ffffc900052cbde0 EFLAGS: 00010246 RAX: 0000000000000001 RBX: ffff88811084d800 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888100042e00 RBP: ffff8881053d8200 R08: ffffc900052cbd68 R09: ffff888105db2000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000002 R13: ffff888104765200 R14: ffff88810eec1748 R15: ffff88810eec1740 FS: 00007fd445fd1740(0000) GS:ffff8897dfc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000060 CR3: 0000000166a00000 CR4: 0000000000350ee0 DR0: ffffffff8437a488 DR1: ffffffff8437a489 DR2: ffffffff8437a48a DR3: ffffffff8437a48b DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: <TASK> nullb_device_power_store+0xd1/0x120 [null_blk] configfs_write_iter+0xb4/0x120 vfs_write+0x2ba/0x3c0 ksys_write+0x5f/0xe0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7fd4460c57a7 Code: 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 RSP: 002b:00007ffd3792a4a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fd4460c57a7 RDX: 0000000000000002 RSI: 000055b43c02e4c0 RDI: 0000000000000001 RBP: 000055b43c02e4c0 R08: 000000000000000a R09: 00007fd44615b4e0 R10: 00007fd44615b3e0 R11: 0000000000000246 R12: 0000000000000002 R13: 00007fd446198520 R14: 0000000000000002 R15: 00007fd446198700 </TASK>

What

Why

The product dereferences a pointer that it expects to be valid but is NULL.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

Why

The product dereferences a pointer that it expects to be valid but is NULL.

How

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation

Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.

No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material

Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.

None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path: local access → NULL Pointer Dereference → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface: Local
Privileges required: Low: a basic authenticated account is required
User interaction: None
Attack complexity: Low: no specialised conditions are recorded
Security boundary: Unchanged: impact remains within the vulnerable component's security authority
Weakness ? CWE means Common Weakness Enumeration: a standard category for the underlying weakness.: CWE-476 ↗
CWE-476: NULL Pointer Dereference. The product dereferences a pointer that it expects to be valid but is NULL.
CVSS vector ? CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land: The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.

CWE-476

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2025-32317Official EUVD mapping

0 linked advisory records.

Official EUVD record

BSI · German · WID-SEC-W-2025-2194Linux Kernel: Mehrere Schwachstellen

Ein lokaler Angreifer kann mehrere Schwachstellen in Linux Kernel ausnutzen, um nicht näher spezifizierte Angriffe durchzuführen.

Official advisory

CERT-FR · French · CERTFR-2025-AVI-1032Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2023-53564 Référence CVE CVE-2023-53566 https://www.cve.org/CVERecord?id=CVE-2023-53566 Référence CVE CVE-2023-53567 https://www.cve.org/CVERecord?id=CVE-2023-53567 Référence CVE CVE-2023-53568 https://www.cve.org/CVERecord?id=CVE-2023-53568 Référence CVE CVE-2023-53570 https://www.cve.org/CVERecord?id=CVE-2023-53570 Référence CVE CVE-2023-53571 https://www.cve.org/CVERecord?id=CVE-2023-53571 Référence CVE CVE-2023-53572 https://www.cve.org/CVERecord?id=CVE-2023-53572 Référence CVE CVE-2023-53574 https://www.cve.org/CVERecord?id=CVE-2023-53574 Référence CVE CVE-2023-53575 https://www.cve.org/CVERecord?id=CVE-2023-53575 Référence CVE CVE-2023-53576 https://www.cve.org/CVERecord?id=CVE-2023-53576 Référence CVE CVE-2023-53577 https://www.cve.org/CVERecord?id=CVE-2023-53577 Référence CVE CVE-2023-53578 https://www.cve.org/CVERecord?id=CVE-2023-53578 Référence CVE CVE-2023-53579 https://www.cve.org/CVERecord?id=CVE-2023-53579 Référence CVE CVE-2023-53580 https://www.cve.org/CVERecord?id=CVE-2023-53580 Référence CVE CVE-2023-53581 https://www.cve.org/CVERecord?id=CVE-2023-53581 Référence CVE CVE-2023-53582 https://www.cve.org/CVERecord?id=CVE-2023-53582 Référence CVE CVE-2023-53583 https://www.cve.org/CVERecord?id=CVE-2023-53583 Référence CVE CVE-2023-53585 https://www.cve.org/CVERecord?id=

Official advisory

Patch and workaround

Operational remediation based on structured source evidence.

Status ? Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.: Patch available
Affected: e50b1e327aeb4b224364aa6f85c1713ff8b3654b < e732a266b973cd4e115e2cc2ea5007119e8a7fbc; e50b1e327aeb4b224364aa6f85c1713ff8b3654b < 35e304dbcefa95237a3d6f94c007bfb10f012b17; e50b1e327aeb4b224364aa6f85c1713ff8b3654b < fd35b7bb6d5a329c427924886949ab51f210200a; e50b1e327aeb4b224364aa6f85c1713ff8b3654b < 651260e563d9f50827dac496dc8a0b9b23d5db1a; e50b1e327aeb4b224364aa6f85c1713ff8b3654b < 63f8793ee60513a09f110ea460a6ff2c33811cdb; 4.20
Fixed: < 4.20; 5.10.181 ≤ 5.10.*; 5.15.113 ≤ 5.15.*; 6.1.30 ≤ 6.1.*; 6.3.4 ≤ 6.3.*; 6.4 ≤ *
Action: Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround: No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.

Evidence and provenance

Published 4 Oct 2025 · Last source change 11 May 2026, 19:47 UTC · CWE-476 · NULL Pointer Dereference

CVE recordCVE.org · 5.2

CVSS sourceNIST NVD

EPSS source

The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.

FIRST · tracked since 2026-08-14

European sourceENISA EUVD · EUVD-2025-32317

Product sourceCNA

Remediation sourceCVE/CNA references

CWE sourceNIST NVD

NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

2025-10-04CVE published

2026-05-11Fixed release or patch reference recorded

ENISA EUVD · EUVD-2025-32317↗CVE authority or vendor reference↗Patch or update reference↗Patch or update reference↗Patch or update reference↗Official CVE record (CNA and ADP data)↗NVD record↗

Technical terms and abbreviations used in this report

CVE: Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS: Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS: Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE: Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA: CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP: Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD: National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT: A computer security incident response team that publishes warnings or coordinates incident response.
PoC: Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF: Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL: Living off the land: abuse of legitimate tools or system functions during an attack.