CVE-2026-23193 [High] | Use-After-Free in Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: scsi: target: iscsi: Fix use-after-free in iscsit_dec_session_usage_count() In iscsit_dec_session_usage_count(), the function calls complete() while holding the sess->session_usage_lock. Similar to the connection usage count logic, the waiter signaled by complete() (e.g., in the session release path) may wake up and free the iscsit_session structure immediately. This creates a race condition where the current thread may attempt to execute spin_unlock_bh() on a session structure that has already been deallocated, resulting in a KASAN slab-use-after-free. To resolve this, release the session_usage_lock before calling complete() to ensure all dereferences of the sess pointer are finished before the waiter is allowed to proceed with deallocation.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.02%	0.24%	+0.22%
2	2026-02-15	—	0.02%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.02%

0.24%

+0.22%

2026-02-15

—

0.02%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
8.8	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. 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.	2.8	5.9	416baaa9-dc9f-4396-8d5f-8c081fb06d67
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

8.8

3.1

HIGH

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

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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.

2.8

5.9

416baaa9-dc9f-4396-8d5f-8c081fb06d67

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-2026-23193

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2026-23193 not yet assigned 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-2026-23193
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2026-23193
`suse`	medium	CVE-2026-23193 severity moderate: SUSE including 153 source package names (2.1.3-6.144:kernel-default-base-6.4.0-41.1.21.18, 2.1.3-7.127:kernel-default-6.4.0-41.1, …), 160 product×package rows across 19 product lines (Container suse/sl-micro/6.0/base-os-container, Container suse/sl-micro/6.0/kvm-os-container, … (19 product lines)): Fixed 123, First Fixed 37.	https://www.suse.com/security/cve/CVE-2026-23193/
`ubuntu`	medium	CVE-2026-23193 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1256 status rows across 8 suites (bionic, focal, jammy, noble, questing, trusty, upstream, xenial): DNE 871, ignored 173, needed 124, released 83, pending 5.	https://ubuntu.com/security/CVE-2026-23193

Affected software / configurations for CVE-2026-23193

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 3.1, < 5.10.250	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.11, < 5.15.200	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.16, < 6.1.163	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.2, < 6.6.124	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.7, < 6.12.70	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.13, < 6.18.10	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	6.19	cpe:2.3:o:linux:linux_kernel:6.19:rc1::::::
linux	linux_kernel	6.19	cpe:2.3:o:linux:linux_kernel:6.19:rc2::::::
linux	linux_kernel	6.19	cpe:2.3:o:linux:linux_kernel:6.19:rc3::::::
linux	linux_kernel	6.19	cpe:2.3:o:linux:linux_kernel:6.19:rc4::::::
linux	linux_kernel	6.19	cpe:2.3:o:linux:linux_kernel:6.19:rc5::::::
linux	linux_kernel	6.19	cpe:2.3:o:linux:linux_kernel:6.19:rc6::::::

References for CVE-2026-23193

URL	Tags
https://git.kernel.org/stable/c/11ebafffce31efc6abeb28c509017976fc49f1ca	Patch
https://git.kernel.org/stable/c/2b64015550a13bcc72910be0565548d9a754d46d	Patch
https://git.kernel.org/stable/c/41b86a9ec037bd3435d68dd3692f0891a207e7e7	Patch
https://git.kernel.org/stable/c/4530f4e4d0e6a207110b0ffed0c911bca43531a4	Patch
https://git.kernel.org/stable/c/84dc6037390b8607c5551047d3970336cb51ba9a	Patch
https://git.kernel.org/stable/c/d8dbdc146e9e9a976931b78715be2e91299049f9	Patch
https://git.kernel.org/stable/c/fd8b0900173307039d3a84644c2fee041a7ed4fb	Patch

URL

CVE-2026-23193 | scsi: target: iscsi: Fix use-after-free in iscsit_dec_session_usage_count()

Exploit prediction scoring system (EPSS) score for CVE-2026-23193

Common vulnerability scoring system (CVSS) metrics for CVE-2026-23193

Weakness enumeration for CVE-2026-23193

OS Trackers for CVE-2026-23193

Affected software / configurations for CVE-2026-23193

References for CVE-2026-23193