CVE-2023-53794: cifs: fix session state check in reconnect to avoid use-after-free issue

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-12-09 · updated 2026-10-15

Description

In the Linux kernel, the following vulnerability has been resolved: cifs: fix session state check in reconnect to avoid use-after-free issue Don't collect exiting session in smb2_reconnect_server(), because it will be released soon. Note that the exiting session will stay in server->smb_ses_list until it complete the cifs_free_ipc() and logoff() and then delete itself from the list.

Affected products

Linux kernel: from 3.10.103 before 3.11; from 3.12.63 before 3.13; from 3.14.74 before 3.15; from 3.16.37 before 3.17; from 3.18.37 before 3.19; from 4.1.28 before 4.2 — fixed in 3.11, 3.13, 3.15, 3.17, 3.19, 4.2

How to fix

Upgrade to a fixed version: Linux kernel 3.11, 3.13, 3.15, 3.17. Check the vendor advisory for mitigations.

References

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