How severe is CVE-2025-38191?

CVE-2025-38191 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-2025-38191 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-38191?

CVE-2025-38191 primarily affects Linux Linux Kernel. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-38191?

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

Does CVE-2025-38191 have an EU (EUVD) identifier?

Yes. CVE-2025-38191 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-20065.

When was CVE-2025-38191 published?

CVE-2025-38191 was published on 2025-07-04 and last updated on 2026-06-17.

CVE-2025-38191

CVE-2025-38191 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% (38th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-20065
Weakness: CWE-476
Affected product: Linux Linux Kernel
Published: 2025-07-04
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix null pointer dereference in destroy_previous_session If client set ->PreviousSessionId on kerberos session setup stage, NULL pointer dereference error will happen. Since sess->user is not set yet, It can pass the user argument as NULL to destroy_previous_session. sess->user will be set in ksmbd_krb5_authenticate(). So this patch move calling destroy_previous_session() after ksmbd_krb5_authenticate().

Frequently asked questions

What is CVE-2025-38191?: In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix null pointer dereference in destroy_previous_session If client set ->PreviousSessionId on kerberos session setup stage, NULL pointer dereference error will happen. Since sess->user is not set yet, It can pass the user argument as NULL to destroy_previous_session. sess->user will be set in ksmbd_krb5_authenticate(). So this patch move calling destroy_previous_session() after ksmbd_krb5_authenticate().
How severe is CVE-2025-38191?: CVE-2025-38191 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-2025-38191 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-38191?: CVE-2025-38191 primarily affects Linux Linux Kernel. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-38191?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-38191 have an EU (EUVD) identifier?: Yes. CVE-2025-38191 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-20065.
When was CVE-2025-38191 published?: CVE-2025-38191 was published on 2025-07-04 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc2:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

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