CVE-2025-38191

ksmbd: fix null pointer dereference in destroy_previous_session

MEDIUM
5.5
CVSS Score
Published: July 4, 2025 at 01:37 PM UTC
Updated: August 5, 2026 at 12:44 PM UTC
2 products affected across 2 vendorsLinux KernelDebian Linux

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Severity
MEDIUM5.5
Exploit prediction
EPSS 1%

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().

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

5.15 ≤ v < 6.1.1425.15 ≤ v < 6.12.355.15 ≤ v < 6.15.45.15 ≤ v < 6.165.15 ≤ v < 6.6.956.13 ≤ v < 6.15.46.2 ≤ v < 6.6.956.7 ≤ v < 6.12.356.16 rc16.16 rc2626e6641f6b467447c81dd7678a69c66f7746cf
Vendor states this is fixed in 076f1adefb9837977af7ed233883842ddc446644 (fixed)
Vendor states this is fixed in 0902625a24eea7fdc187faa5d97df244d159dd6e (fixed)
Vendor states this is fixed in 1193486dffb7432a09f57f5d09049b4d4123538b (fixed)
Vendor states this is fixed in 281afc52e2961cd5dd8326ebc9c5bc40904c0468 (fixed)
Vendor states this is fixed in 7ac5b66acafcc9292fb935d7e03790f2b8b2dc0e (fixed)
Vendor states this is fixed in 5.15 (unaffected)
Vendor states this is fixed in 6.1.142 (unaffected)
Vendor states this is fixed in 6.12.35 (unaffected)
Vendor states this is fixed in 6.15.4 (unaffected)
Vendor states this is fixed in 6.16 (unaffected)
Vendor states this is fixed in 6.6.95 (unaffected)

References (7)

Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/076f1adefb9837977af7ed233883842ddc446644
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/0902625a24eea7fdc187faa5d97df244d159dd6e
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/1193486dffb7432a09f57f5d09049b4d4123538b
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/281afc52e2961cd5dd8326ebc9c5bc40904c0468
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/7ac5b66acafcc9292fb935d7e03790f2b8b2dc0e
Third Party Advisory
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://www.zerodayinitiative.com/advisories/ZDI-25-610/
Third Party Advisory
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-476

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