NVD / CVE Program· CNA Linux

CVE-2023-53608: nilfs2: fix potential UAF of struct nilfs_sc_info in nilfs_segctor_thread()

Noroxi assessment

Priority: Monitor (action score 31/100)

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: 0.15% (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 034cce77d52ba013ce62b4f5258c29907eb1ada5, 0dbf0e64b91ee8fcb278aea93eb06fc7d56ecbcc, 613bf23c070d11c525268f2945aa594704a9b764.

Low priority for now. Upgrade to Linux Linux 034cce77d52ba013ce62b4f5258c29907eb1ada5, 0dbf0e64b91ee8fcb278aea93eb06fc7d56ecbcc, 613bf23c070d11c525268f2945aa594704a9b764 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: nilfs2: fix potential UAF of struct nilfs_sc_info in nilfs_segctor_thread() The finalization of nilfs_segctor_thread() can race with nilfs_segctor_kill_thread() which terminates that thread, potentially causing a use-after-free BUG as KASAN detected. At the end of nilfs_segctor_thread(), it assigns NULL to "sc_task" member of "struct nilfs_sc_info" to indicate the thread has finished, and then notifies nilfs_segctor_kill_thread() of this using waitqueue "sc_wait_task" on the struct nilfs_sc_info. However, here, immediately after the NULL assignment to "sc_task", it is possible that nilfs_segctor_kill_thread() will detect it and return to continue the deallocation, freeing the nilfs_sc_info structure before the thread does the notification. This fixes the issue by protecting the NULL assignment to "sc_task" and its notification, with spinlock "sc_state_lock" of the struct nilfs_sc_info. Since nilfs_segctor_kill_thread() does a final check to see if "sc_task" is NULL with "sc_state_lock" locked, this can eliminate the race.

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

BDU:2026-04586

Published: Oct 4, 2025
Updated: Aug 5, 2026
EPSS: 0.1% · 4th percentile
CWE: CWE-416

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 31 / 40 · 7.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.1%

CNA vs NVD score

NVD: 7.8
CNA · Linux: 7.8; agree

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

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

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Noroxi analysis

What does it mean in your environment?

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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.

Vendor	Product	CPE
linux	linux kernel	cpe:2.3:o:linux:linux_kernel

Affected versions

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

linux linux kernel2.6.30 and later · before 4.14.313
linux linux kernel4.15 and later · before 4.19.281
linux linux kernel4.20 and later · before 5.4.241
linux linux kernel5.5 and later · before 5.10.178
linux linux kernel5.11 and later · before 5.15.107
linux linux kernel5.16 and later · before 6.1.24
linux linux kernel6.2 and later · before 6.2.11
linux linux kernel6.3

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
- 2.6.30affected
- 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 and later · before 034cce77d52ba013ce62b4f5258c29907eb1ada5affected · git
- 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 and later · before 0dbf0e64b91ee8fcb278aea93eb06fc7d56ecbccaffected · git
- 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 and later · before 613bf23c070d11c525268f2945aa594704a9b764affected · git
- 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 and later · before f32297dba338dc06d62286dedb3cdbd5175b1719affected · git
- 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 and later · before 92684e02654c91a61a0b0561433b710bcece19feaffected · git
- 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 and later · before bae009a2f1b7c2011d2e92d8c84868d315c0b97eaffected · git
- 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 and later · before b4d80bd6370b81a1725b6b8f7894802c23a14e9faffected · git
- 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 and later · before 6be49d100c22ffea3287a4b19d7639d259888e33affected · git
- before 2.6.30not affected · semver

Package-level exposure

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

Ecosystem	Package	Affected range	Fix
Debian:12	linux	before 6.1.25-1	6.1.25-1

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
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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-2023-53605Oct 4, 2025 · drm: amd: display: Fix memory leakage
22Monitor
← EarlierCVE-2023-53607Oct 4, 2025 · ALSA: ymfpci: Fix BUG_ON in probe function
22Monitor
Later →CVE-2023-53610Oct 4, 2025 · irqchip: Fix refcount leak in platform_irqchip_probe
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 / package	Fixed version	Source
Linux Linux	034cce77d52ba013ce62b4f5258c29907eb1ada5	Vendor (CNA)
Linux Linux	0dbf0e64b91ee8fcb278aea93eb06fc7d56ecbcc	Vendor (CNA)
Linux Linux	613bf23c070d11c525268f2945aa594704a9b764	Vendor (CNA)
Linux Linux	6be49d100c22ffea3287a4b19d7639d259888e33	Vendor (CNA)
Linux Linux	92684e02654c91a61a0b0561433b710bcece19fe	Vendor (CNA)
Linux Linux	b4d80bd6370b81a1725b6b8f7894802c23a14e9f	Vendor (CNA)
Linux Linux	bae009a2f1b7c2011d2e92d8c84868d315c0b97e	Vendor (CNA)
Linux Linux	f32297dba338dc06d62286dedb3cdbd5175b1719	Vendor (CNA)
debian:linux	6.1.25-1 · Debian:12	Package 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.

No nightly-computed relations.

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: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-416 · Use After Free

CVSS vector

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

nvd-primary

Root cause

After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.

The bug in code

The whole CWE-416 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1free(dev->buf);
2/* ... another thread is still running ... */
3process(dev->buf);

Fixed

1lock(&dev->lock);
2free(dev->buf);
3dev->buf = NULL;
4unlock(&dev->lock);

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

Fix✗ → ✓Sep 28, 2026, 10:09 PM UTC

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

References

git.kernel.org/stable/c/034cce77d52ba013ce62b4f5258c29907eb1ada5

Show all references (7 more)

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

All records