CVE-2025-68817 [High] | Use-After-Free in Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in ksmbd_tree_connect_put under concurrency Under high concurrency, A tree-connection object (tcon) is freed on a disconnect path while another path still holds a reference and later executes *_put()/write on it.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-02-27	0.06%	0.01%	-0.04%
2	2026-02-10	0.02%	0.06%	+0.04%
3	2026-01-14	—	0.02%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-02-27

0.06%

0.01%

-0.04%

2026-02-10

0.02%

0.06%

+0.04%

2026-01-14

—

0.02%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.8	3.1	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	5.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.8

3.1

HIGH

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

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

5.9

[email protected]

OS Trackers for CVE-2025-68817

vendor	priority	summary	link
`debian`	unimportant	CVE-2025-68817 unimportant priority: Debian including 2 source packages (linux, linux-6.1), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 6.	https://security-tracker.debian.org/tracker/CVE-2025-68817
`redhat`	—	—	https://access.redhat.com/security/cve/CVE-2025-68817
`suse`	medium	CVE-2025-68817 severity moderate: SUSE including 26 source package names (cluster-md-kmp-default, dlm-kmp-default, …), 235 product×package rows across 43 product lines (SUSE Linux Enterprise High Availability Extension 15 SP7, SUSE Linux Enterprise High Availability Extension 16.0, … (43 product lines)): Known Not Affected 235.	https://www.suse.com/security/cve/CVE-2025-68817/
`ubuntu`	medium	CVE-2025-68817 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1562 status rows across 10 suites (bionic, focal, jammy, noble, plucky, questing, resolute, trusty, upstream, xenial): DNE 1157, ignored 183, released 147, needed 50, pending 15, not-affected 10.	https://ubuntu.com/security/CVE-2025-68817

Affected software / configurations for CVE-2025-68817

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 5.15.145, < 5.15.199	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.1.71, < 6.1.160	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.6.1, < 6.6.120	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.7, < 6.12.64	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.13, < 6.18.3	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	6.6	cpe:2.3:o:linux:linux_kernel:6.6:-::::::
linux	linux_kernel	6.6	cpe:2.3:o:linux:linux_kernel:6.6:rc5::::::
linux	linux_kernel	6.6	cpe:2.3:o:linux:linux_kernel:6.6:rc6::::::
linux	linux_kernel	6.6	cpe:2.3:o:linux:linux_kernel:6.6:rc7::::::

References for CVE-2025-68817

URL	Tags
https://git.kernel.org/stable/c/063cbbc6f595ea36ad146e1b7d2af820894beb21	Patch
https://git.kernel.org/stable/c/21a3d01fc6db5129f81edb0ab7cb94fd758bcbea	Patch
https://git.kernel.org/stable/c/446beed646b2e426dd53d27358365f8678e1dd01	Patch
https://git.kernel.org/stable/c/b39a1833cc4a2755b02603eec3a71a85e9dff926	Patch
https://git.kernel.org/stable/c/d092de8a26c952379ded8e6b0bda31d89befac1a	Patch
https://git.kernel.org/stable/c/d64977495e44855f2b28d8ce56107c963a7a50e4	Patch

URL

CVE-2025-68817 | ksmbd: fix use-after-free in ksmbd_tree_connect_put under concurrency

Exploit prediction scoring system (EPSS) score for CVE-2025-68817

Common vulnerability scoring system (CVSS) metrics for CVE-2025-68817

Weakness enumeration for CVE-2025-68817

OS Trackers for CVE-2025-68817

Affected software / configurations for CVE-2025-68817

References for CVE-2025-68817