Vulnerability-Lookup

FKIE_CVE-2026-31476

Vulnerability from fkie_nvd - Published: 2026-04-22 14:16 - Updated: 2026-06-01 17:16

Severity

8.2 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: do not expire session on binding failure When a multichannel session binding request fails (e.g. wrong password), the error path unconditionally sets sess->state = SMB2_SESSION_EXPIRED. However, during binding, sess points to the target session looked up via ksmbd_session_lookup_slowpath() -- which belongs to another connection's user. This allows a remote attacker to invalidate any active session by simply sending a binding request with a wrong password (DoS). Fix this by skipping session expiration when the failed request was a binding attempt, since the session does not belong to the current connection. The reference taken by ksmbd_session_lookup_slowpath() is still correctly released via ksmbd_user_session_put().

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/1d1888b4a7aec518b707f6eca0bf08992c0e8da3	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/4642ea35c03cf3d3558c009df4757cdb7af3f82d
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/6fafc4c4238e538969f1375f9ecdc6587c53f1cc	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/9bbb19d21ded7d78645506f20d8c44895e3d0fb9	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/a897064a457056acb976e20e3007cdf553de340f	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/e0e5edc81b241c70355217de7e120c97c3429deb	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/f5300690c23c5ac860499bb37dbc09cf43fd62e6	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	5.15
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

To clipboard

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CVE-2026-31476 (GCVE-0-2026-31476)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:54 – Updated: 2026-06-01 16:11

Title

ksmbd: do not expire session on binding failure

Summary

Severity

8.2 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

Assigner

Linux

References

7 references

URL	Tags
https://git.kernel.org/stable/c/4642ea35c03cf3d35…
https://git.kernel.org/stable/c/f5300690c23c5ac86…
https://git.kernel.org/stable/c/6fafc4c4238e53896…
https://git.kernel.org/stable/c/1d1888b4a7aec518b…
https://git.kernel.org/stable/c/a897064a457056acb…
https://git.kernel.org/stable/c/e0e5edc81b241c703…
https://git.kernel.org/stable/c/9bbb19d21ded7d786…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < 4642ea35c03cf3d3558c009df4757cdb7af3f82d (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < f5300690c23c5ac860499bb37dbc09cf43fd62e6 (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < 6fafc4c4238e538969f1375f9ecdc6587c53f1cc (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < 1d1888b4a7aec518b707f6eca0bf08992c0e8da3 (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < a897064a457056acb976e20e3007cdf553de340f (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < e0e5edc81b241c70355217de7e120c97c3429deb (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < 9bbb19d21ded7d78645506f20d8c44895e3d0fb9 (git)
Linux	Linux	Affected: 5.15 Unaffected: 0 , < 5.15 (semver) Unaffected: 5.15.209 , ≤ 5.15.* (semver) Unaffected: 6.1.168 , ≤ 6.1.* (semver) Unaffected: 6.6.131 , ≤ 6.6.* (semver) Unaffected: 6.12.80 , ≤ 6.12.* (semver) Unaffected: 6.18.21 , ≤ 6.18.* (semver) Unaffected: 6.19.11 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

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          "programFiles": [
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2026-31476

CVE-2026-31476 (GCVE-0-2026-31476)

Tags

Sightings

Nomenclature