Skip to content
Noroxi
NVD / CVE Program· CNA Linux

CVE-2023-53513: nbd: fix incomplete validation of ioctl arg

Noroxi assessment

Priority: Monitor (action score 22/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.14% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 52851d0c3354b397c11d31dfeb8b2a2fc85a0002, 55793ea54d77719a071b1ccc05a05056e3b5e009, fab766c8a1aff715bce7075aab40e780266f8e1a.

Low priority for now. Upgrade to Linux Linux 52851d0c3354b397c11d31dfeb8b2a2fc85a0002, 55793ea54d77719a071b1ccc05a05056e3b5e009, fab766c8a1aff715bce7075aab40e780266f8e1a or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: nbd: fix incomplete validation of ioctl arg We tested and found an alarm caused by nbd_ioctl arg without verification. The UBSAN warning calltrace like below: UBSAN: Undefined behaviour in fs/buffer.c:1709:35 signed integer overflow: -9223372036854775808 - 1 cannot be represented in type 'long long int' CPU: 3 PID: 2523 Comm: syz-executor.0 Not tainted 4.19.90 #1 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x0/0x3f0 arch/arm64/kernel/time.c:78 show_stack+0x28/0x38 arch/arm64/kernel/traps.c:158 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x170/0x1dc lib/dump_stack.c:118 ubsan_epilogue+0x18/0xb4 lib/ubsan.c:161 handle_overflow+0x188/0x1dc lib/ubsan.c:192 __ubsan_handle_sub_overflow+0x34/0x44 lib/ubsan.c:206 __block_write_full_page+0x94c/0xa20 fs/buffer.c:1709 block_write_full_page+0x1f0/0x280 fs/buffer.c:2934 blkdev_writepage+0x34/0x40 fs/block_dev.c:607 __writepage+0x68/0xe8 mm/page-writeback.c:2305 write_cache_pages+0x44c/0xc70 mm/page-writeback.c:2240 generic_writepages+0xdc/0x148 mm/page-writeback.c:2329 blkdev_writepages+0x2c/0x38 fs/block_dev.c:2114 do_writepages+0xd4/0x250 mm/page-writeback.c:2344 The reason for triggering this warning is __block_write_full_page() -> i_size_read(inode) - 1 overflow. inode->i_size is assigned in __nbd_ioctl() -> nbd_set_size() -> bytesize. We think it is necessary to limit the size of arg to prevent errors. Moreover, __nbd_ioctl() -> nbd_add_socket(), arg will be cast to int. Assuming the value of arg is 0x80000000000000001) (on a 64-bit machine), it will become 1 after the coercion, which will return unexpected results. Fix it by adding checks to prevent passing in too large numbers.

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
Oct 1, 2025
Updated
Jun 17, 2026
EPSS
0.1% · 4th percentile

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2023-53513

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for linux records

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel4.1 and later · before 5.15.113
  • linux linux kernel5.16 and later · before 6.1.30
  • linux linux kernel6.2 and later · before 6.3.4

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 4.1affected
    • b9c495bb6d8edc719fd23af2ac67de8303cfc1e8 and later · before 52851d0c3354b397c11d31dfeb8b2a2fc85a0002affected · git
    • b9c495bb6d8edc719fd23af2ac67de8303cfc1e8 and later · before fab766c8a1aff715bce7075aab40e780266f8e1aaffected · git
    • b9c495bb6d8edc719fd23af2ac67de8303cfc1e8 and later · before ffb75ffaa68723276365d0f9d00b03362b750657affected · git
    • b9c495bb6d8edc719fd23af2ac67de8303cfc1e8 and later · before 55793ea54d77719a071b1ccc05a05056e3b5e009affected · git
    • before 4.1not affected · semver
    • 5.15.113 and later · up to and including 5.15.*not affected · semver
    • 6.1.30 and later · up to and including 6.1.*not affected · semver
    • 6.3.4 and later · up to and including 6.3.*not affected · semver
    • 6.4 and laternot affected · original_commit_for_fix

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:8bpftoolbefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernelbefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-abi-stablelistsbefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-corebefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-cross-headersbefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-debugbefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-debug-corebefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-debug-develbefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-debug-modulesbefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-debug-modules-extrabefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-develbefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-docbefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-headersbefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-modulesbefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-modules-extrabefore 4.18.0-553.87.1.el8_104.18.0-553.87.1.el8_10
AlmaLinux:8kernel-rtbefore 4.18.0-553.87.1.rt7.428.el8_104.18.0-553.87.1.rt7.428.el8_10
AlmaLinux:8kernel-rt-corebefore 4.18.0-553.87.1.rt7.428.el8_104.18.0-553.87.1.rt7.428.el8_10
AlmaLinux:8kernel-rt-debugbefore 4.18.0-553.87.1.rt7.428.el8_104.18.0-553.87.1.rt7.428.el8_10
AlmaLinux:8kernel-rt-debug-corebefore 4.18.0-553.87.1.rt7.428.el8_104.18.0-553.87.1.rt7.428.el8_10
AlmaLinux:8kernel-rt-debug-develbefore 4.18.0-553.87.1.rt7.428.el8_104.18.0-553.87.1.rt7.428.el8_10
AlmaLinux:8kernel-rt-debug-modulesbefore 4.18.0-553.87.1.rt7.428.el8_104.18.0-553.87.1.rt7.428.el8_10
AlmaLinux:8kernel-rt-debug-modules-extrabefore 4.18.0-553.87.1.rt7.428.el8_104.18.0-553.87.1.rt7.428.el8_10
AlmaLinux:8kernel-rt-develbefore 4.18.0-553.87.1.rt7.428.el8_104.18.0-553.87.1.rt7.428.el8_10
AlmaLinux:8kernel-rt-modulesbefore 4.18.0-553.87.1.rt7.428.el8_104.18.0-553.87.1.rt7.428.el8_10

+96

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2023-53508Oct 1, 2025 · ublk: fail to start device if queue setup is interrupted
    31Monitor
  • ← EarlierCVE-2023-53510Oct 1, 2025 · scsi: ufs: core: Fix handling of lrbp->cmd
    31Monitor
  • Later →CVE-2023-53519Oct 1, 2025 · media: v4l2-mem2mem: add lock to protect parameter num_rdy
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux52851d0c3354b397c11d31dfeb8b2a2fc85a0002Vendor (CNA)
Linux Linux55793ea54d77719a071b1ccc05a05056e3b5e009Vendor (CNA)
Linux Linuxfab766c8a1aff715bce7075aab40e780266f8e1aVendor (CNA)
Linux Linuxffb75ffaa68723276365d0f9d00b03362b750657Vendor (CNA)
almalinux:bpftool4.18.0-553.87.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel4.18.0-553.87.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-core4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-core4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-devel4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules-extra4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-devel4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-modules4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-modules-extra4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8Package registry (OSV)
debian:linux6.1.37-1 · Debian:12Package registry (OSV)
red hat:bpftool-debuginfo0:7.0.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-debuginfo0:5.14.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel0:5.14.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel-matched0:5.14.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
red hat:kernel-64k-debuginfo0:5.14.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
red hat:kernel-64k-devel0:5.14.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
red hat:kernel-64k-devel-matched0:5.14.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
red hat:kernel-debug-debuginfo0:5.14.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
red hat:kernel-debug-devel0:5.14.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
red hat:kernel-debug-devel-matched0:5.14.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
red hat:kernel-debuginfo0:5.14.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
red hat:kernel-debuginfo-common-aarch640:5.14.0-284.148.1.el9_2 · Red Hat:rhel_e4s:9.2::appstreamPackage registry (OSV)
rocky linux:kernel0:4.18.0-553.87.1.el8_10 · Rocky Linux:8Package registry (OSV)

+1

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-43185217 days apartksmbd: fix signededness bug in smb_direct_prepare_negotiation()
    39Monitor
  • CVE-2025-3845968 days apartatm: clip: Fix infinite recursive call of clip_push().
    31Monitor
  • CVE-2026-53202267 days apartaccel/ivpu: Fix signed integer truncation in IPC receive
    31Monitor
  • CVE-2026-53267267 days apartnetfilter: nft_ct: bail out on template ct in get eval
    31Monitor
  • CVE-2024-35886500 days apartipv6: Fix infinite recursion in fib6_dump_done().
    31Monitor
  • CVE-2026-53395291 days apartnfsd: fix dead ACL conflict guard in nfsd4_create
    30Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-674 · Uncontrolled Recursion

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records