How severe is CVE-2023-53566?

CVE-2023-53566 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-53566 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-53566?

CVE-2023-53566 primarily affects Linux Linux Kernel. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-53566?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2023-53566 have an EU (EUVD) identifier?

Yes. CVE-2023-53566 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-32293.

When was CVE-2023-53566 published?

CVE-2023-53566 was published on 2025-10-04 and last updated on 2026-06-17.

CVE-2023-53566

CVE-2023-53566 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-32293
Weakness: CWE-476
Affected product: Linux Linux Kernel
Published: 2025-10-04
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_rbtree: fix null deref on element insertion There is no guarantee that rb_prev() will not return NULL in nft_rbtree_gc_elem(): general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] nft_add_set_elem+0x14b0/0x2990 nf_tables_newsetelem+0x528/0xb30 Furthermore, there is a possible use-after-free while iterating, 'node' can be free'd so we need to cache the next value to use.

Frequently asked questions

What is CVE-2023-53566?: In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_rbtree: fix null deref on element insertion There is no guarantee that rb_prev() will not return NULL in nft_rbtree_gc_elem(): general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] nft_add_set_elem+0x14b0/0x2990 nf_tables_newsetelem+0x528/0xb30 Furthermore, there is a possible use-after-free while iterating, 'node' can be free'd so we need to cache the next value to use.
How severe is CVE-2023-53566?: CVE-2023-53566 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-53566 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-53566?: CVE-2023-53566 primarily affects Linux Linux Kernel. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-53566?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2023-53566 have an EU (EUVD) identifier?: Yes. CVE-2023-53566 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-32293.
When was CVE-2023-53566 published?: CVE-2023-53566 was published on 2025-10-04 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:rc7:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:rc8:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.4:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.4:rc2:*:*:*:*:*:*

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