NVD / CVE Program· CNA Linux

CVE-2023-52983: block, bfq: fix uaf for bfqq in bic_set_bfqq()

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: 0.28% (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 5.15.93, 511c922c5bf6c8a166bea826e702336bc2424140, 6.1.

Low priority for now. Upgrade to Linux Linux 5.15.93, 511c922c5bf6c8a166bea826e702336bc2424140, 6.1 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: block, bfq: fix uaf for bfqq in bic_set_bfqq() After commit 64dc8c732f5c ("block, bfq: fix possible uaf for 'bfqq->bic'"), bic->bfqq will be accessed in bic_set_bfqq(), however, in some context bic->bfqq will be freed, and bic_set_bfqq() is called with the freed bic->bfqq. Fix the problem by always freeing bfqq after bic_set_bfqq().

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

Published: Mar 27, 2025
Updated: Aug 5, 2026
EPSS: 0.2% · 20th percentile
CWE: CWE-416

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 31 / 40 · 7.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.2%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · Linux: 7.8; 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.

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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?

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.

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 kernel5.15.86 and later · before 5.15.93
linux linux kernel6.1.2 and later · before 6.1.11
linux linux kernel6.0.16

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
- b22fd72bfebda3956efc4431b60ddfc0a51e03e0affected
- 5533742c7cb1bc9b1f0bf401cc397d44a3a9e07a and later · before 7f77f3dab5066a7c9da73d72d1eee895ff84a8d5affected · git
- 094f3d9314d67691cb21ba091c1b528f6e3c4893 and later · before 511c922c5bf6c8a166bea826e702336bc2424140affected · git
- 761564d93c8265f65543acf0a576b32d66bfa26a and later · before cb1876fc33af26d00efdd473311f1b664c77c44eaffected · git
- 64dc8c732f5c2b406cc752e6aaa1bd5471159cab and later · before b600de2d7d3a16f9007fad1bdae82a3951a26af2affected · git
- 6.0.16 and later · before 6.1affected · semver
- 5.15.86 and later · before 5.15.93affected · semver
- 6.1.2 and later · before 6.1.11affected · 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 6.1.11-1	6.1.11-1
SUSE:Linux Enterprise Micro 5.2	kernel-default	before 5.3.18-150300.59.235.1	5.3.18-150300.59.235.1
SUSE:Linux Enterprise Micro 5.2	kernel-default-base	before 5.3.18-150300.59.235.1.150300.18.140.1	5.3.18-150300.59.235.1.150300.18.140.1
SUSE:Linux Enterprise Micro 5.2	kernel-rt	before 5.3.18-150300.235.1	5.3.18-150300.235.1
SUSE:Linux Enterprise Micro 5.2	kernel-source-rt	before 5.3.18-150300.235.1	5.3.18-150300.235.1

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-2023-52978Mar 27, 2025 · riscv: kprobe: Fixup kernel panic when probing an illegal position
22Monitor
← EarlierCVE-2023-52980Mar 27, 2025 · block: ublk: extending queue_size to fix overflow
31Monitor
Later →CVE-2023-52984Mar 27, 2025 · net: phy: dp83822: Fix null pointer access on DP83825/DP83826 devices
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	5.15.93	Vendor (CNA)
Linux Linux	511c922c5bf6c8a166bea826e702336bc2424140	Vendor (CNA)
Linux Linux	6.1	Vendor (CNA)
Linux Linux	6.1.11	Vendor (CNA)
Linux Linux	7f77f3dab5066a7c9da73d72d1eee895ff84a8d5	Vendor (CNA)
Linux Linux	b600de2d7d3a16f9007fad1bdae82a3951a26af2	Vendor (CNA)
Linux Linux	cb1876fc33af26d00efdd473311f1b664c77c44e	Vendor (CNA)
debian:linux	6.1.11-1 · Debian:12	Package registry (OSV)
suse:kernel-default	5.3.18-150300.59.235.1 · SUSE:Linux Enterprise Micro 5.2	Package registry (OSV)
suse:kernel-default-base	5.3.18-150300.59.235.1.150300.18.140.1 · SUSE:Linux Enterprise Micro 5.2	Package registry (OSV)
suse:kernel-rt	5.3.18-150300.235.1 · SUSE:Linux Enterprise Micro 5.2	Package registry (OSV)
suse:kernel-source-rt	5.3.18-150300.235.1 · SUSE:Linux Enterprise Micro 5.2	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-secondary

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, 10:10 PM UTC

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

References

git.kernel.org/stable/c/511c922c5bf6c8a166bea826e702336bc2424140

Show all references (3 more)

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

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