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NVD / CVE Program· CNA Linux

CVE-2026-53309: ocfs2/dlm: fix off-by-one in dlm_match_regions() region comparison

Noroxi assessment

Priority: Monitor (action score 39/100)

  • 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: 0.39% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 01b61e8dda9b0fdb0d4cda43de25f4e390554d7b, 1fb7f356547d9688822315cd2b205ff0bd5429b4, 2a0673836f019e7c032acbf48d022d5ccf02a845.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 01b61e8dda9b0fdb0d4cda43de25f4e390554d7b, 1fb7f356547d9688822315cd2b205ff0bd5429b4, 2a0673836f019e7c032acbf48d022d5ccf02a845 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: ocfs2/dlm: fix off-by-one in dlm_match_regions() region comparison The local-vs-remote region comparison loop uses '<=' instead of '<', causing it to read one entry past the valid range of qr_regions. The other loops in the same function correctly use '<'. Fix the loop condition to use '<' for consistency and correctness.

CriticalCVSS 9.8 · v3.1—No exploit Fix available
Published
Jun 26, 2026
Updated
Aug 5, 2026
EPSS
0.3% · 34th percentile

Report tools

JSON

Action score

39

Monitor

Low priority for now.

CVSS
39 / 40 · 9.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CNA vs NVD score

NVD
—
CNA · Linux
9.8
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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-2026-53309

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

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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.

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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 kernel2.6.37 and later · before 5.10.258
  • linux linux kernel5.11 and later · before 5.15.209
  • linux linux kernel5.16 and later · before 6.1.175
  • linux linux kernel6.2 and later · before 6.6.141
  • linux linux kernel6.7 and later · before 6.12.91
  • linux linux kernel6.13 and later · before 6.18.33
  • linux linux kernel6.19 and later · before 7.0.10

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

    • 2.6.37affected
    • ea2034416b54700e30371f2ad6517cbb94674083 and later · before 760ab35040aca8399021fdb9ff1db1089feb7194affected · git
    • ea2034416b54700e30371f2ad6517cbb94674083 and later · before c60a2710b73838d250cda57344c049b89abc5d52affected · git
    • ea2034416b54700e30371f2ad6517cbb94674083 and later · before 2a0673836f019e7c032acbf48d022d5ccf02a845affected · git
    • ea2034416b54700e30371f2ad6517cbb94674083 and later · before 819d8ebad3200a53de99bd7e297bc428e41ced54affected · git
    • ea2034416b54700e30371f2ad6517cbb94674083 and later · before d5403ae28085761d58b555645bc7d5feadb10073affected · git
    • ea2034416b54700e30371f2ad6517cbb94674083 and later · before 1fb7f356547d9688822315cd2b205ff0bd5429b4affected · git
    • ea2034416b54700e30371f2ad6517cbb94674083 and later · before 426cd8eedac89b86148d4478990eeef16e8a2520affected · git
    • ea2034416b54700e30371f2ad6517cbb94674083 and later · before 01b61e8dda9b0fdb0d4cda43de25f4e390554d7baffected · git
    • before 2.6.37not affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.176-16.1.176-1
Debian:13linuxbefore 6.12.94-16.12.94-1
Debian:14linuxbefore 7.0.10-17.0.10-1

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-2026-53306Jun 26, 2026 · tty: hvc_iucv: fix off-by-one in number of supported devices
    22Monitor
  • ← EarlierCVE-2026-53307Jun 26, 2026 · pinctrl: pinconf-generic: Fully validate 'pinmux' property
    22Monitor
  • Later →CVE-2026-53310Jun 26, 2026 · soc/tegra: cbb: Fix cross-fabric target timeout lookup
    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 Linux01b61e8dda9b0fdb0d4cda43de25f4e390554d7bVendor (CNA)
Linux Linux1fb7f356547d9688822315cd2b205ff0bd5429b4Vendor (CNA)
Linux Linux2a0673836f019e7c032acbf48d022d5ccf02a845Vendor (CNA)
Linux Linux426cd8eedac89b86148d4478990eeef16e8a2520Vendor (CNA)
Linux Linux760ab35040aca8399021fdb9ff1db1089feb7194Vendor (CNA)
Linux Linux819d8ebad3200a53de99bd7e297bc428e41ced54Vendor (CNA)
Linux Linuxc60a2710b73838d250cda57344c049b89abc5d52Vendor (CNA)
Linux Linuxd5403ae28085761d58b555645bc7d5feadb10073Vendor (CNA)
debian:linux6.1.176-1 · Debian:12Package registry (OSV)

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-2026-530882 days apartnet: bcmgenet: fix off-by-one in bcmgenet_put_txcb
    39Monitor
  • CVE-2026-6404723 days apartnet: tls: fix off-by-one in sg_chain entry count for wrapped sk_msg ring
    39Monitor
  • CVE-2026-530362 days apartbpf, arm64: Fix off-by-one in check_imm signed range check
    31Monitor
  • CVE-2026-5290717 days apartmedia: rockchip: rkcif: fix off by one bugs
    31Monitor
  • CVE-2024-57990485 days apartwifi: mt76: mt7925: fix off by one in mt7925_load_clc()
    31Monitor
  • CVE-2026-533060 days aparttty: hvc_iucv: fix off-by-one in number of supported devices
    22Monitor

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).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-193 · Off-by-one Error

CVSS vector

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

nvd-secondary

Attack context

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

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

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

References

Show all references (7 more)

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

All records