How severe is CVE-2023-52440?

CVE-2023-52440 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-52440 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 22% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-52440?

CVE-2023-52440 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-52440?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2023-52440 have an EU (EUVD) identifier?

Yes. CVE-2023-52440 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-57065.

When was CVE-2023-52440 published?

CVE-2023-52440 was published on 2024-02-21 and last updated on 2026-08-15.

CVE-2023-52440

CVE-2023-52440 is a critical-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 22% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-119.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 22% (98th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-57065
Weakness: CWE-119
Affected product: Linux Linux Kernel
Published: 2024-02-21
Last modified: 2026-08-15

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix slub overflow in ksmbd_decode_ntlmssp_auth_blob() If authblob->SessionKey.Length is bigger than session key size(CIFS_KEY_SIZE), slub overflow can happen in key exchange codes. cifs_arc4_crypt copy to session key array from SessionKey from client.

Frequently asked questions

What is CVE-2023-52440?: In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix slub overflow in ksmbd_decode_ntlmssp_auth_blob() If authblob->SessionKey.Length is bigger than session key size(CIFS_KEY_SIZE), slub overflow can happen in key exchange codes. cifs_arc4_crypt copy to session key array from SessionKey from client.
How severe is CVE-2023-52440?: CVE-2023-52440 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-52440 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 22% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-52440?: CVE-2023-52440 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-52440?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2023-52440 have an EU (EUVD) identifier?: Yes. CVE-2023-52440 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-57065.
When was CVE-2023-52440 published?: CVE-2023-52440 was published on 2024-02-21 and last updated on 2026-08-15.

References

Affected products (1)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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