CVE-2026-43458

In the Linux kernel, the following vulnerability has been resolved: serial: caif: hold tty->link reference in ldisc_open and ser_release A reproducer triggers a KASAN slab-use-after-free in pty_write_room() when caif_serial's TX path calls tty_write_room(). The faulting access is on tty->link->port. Hold an extra kref on tty->link for the lifetime of the caif_serial line discipline: get it in ldisc_open() and drop it in ser_release(), and also drop it on the ldisc_open() error path. With this change applied, the reproducer no longer triggers the UAF in my testing.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/23a3ac2e2262a291498567418227b99e1f3606b1	Patch
https://git.kernel.org/stable/c/27e43356d0defb9fc7fa25265219a3ffeb7b3e98	Patch
https://git.kernel.org/stable/c/288598d80a068a0e9281de35bcb4ce495f189e2a	Patch
https://git.kernel.org/stable/c/35b58d3bc716ebb9ebd10fe1cac8c1177242511c	Patch
https://git.kernel.org/stable/c/52135420e9f75853ea0c6cea7b736e3e98495f7d	Patch
https://git.kernel.org/stable/c/8460187b4852fd00bd1c76394358053f3fa4d089	Patch
https://git.kernel.org/stable/c/97a0bb491cae39478c6225381f14e9ac67b7bba7	Patch
https://git.kernel.org/stable/c/ca2ceba983bb23ea0202c2882d963253416654a3	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc2::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc3::::::

History

No history.

Information

Published : 2026-05-08 15:16

Updated : 2026-06-17 10:49

NVD link : CVE-2026-43458

Mitre link : CVE-2026-43458

CVE.ORG link : CVE-2026-43458

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-416

Use After Free

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The faulting access\nis on tty->link->port.\n\nHold an extra kref on tty->link for the lifetime of the caif_serial line\ndiscipline: get it in ldisc_open() and drop it in ser_release(), and\nalso drop it on the ldisc_open() error path.\n\nWith this change applied, the reproducer no longer triggers the UAF in\nmy testing."}], "lastModified": "2026-06-17T10:49:38.410", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "01B7CC59-B567-4F40-ABCE-0E98C6B3D80D", "versionEndExcluding": "5.10.253", "versionStartIncluding": "2.6.35"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "20DDB3E9-AABF-4107-ADB0-5362AA067045", "versionEndExcluding": "5.15.203", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2EDC6BAF-B710-4E26-B6AA-D68922EE7B43", "versionEndExcluding": "6.1.167", "versionStartIncluding": "5.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "C57BB918-DF28-46B3-94F7-144176841267", "versionEndExcluding": "6.6.130", "versionStartIncluding": "6.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "28D591F5-B196-4CC9-905C-DC80F116E7A8", "versionEndExcluding": "6.12.78", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D394AC60-6F28-435F-872A-CCDF384B8331", "versionEndExcluding": "6.18.19", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E825E7C3-FEAC-4FD3-8A81-78D7387948C9", "versionEndExcluding": "6.19.9", "versionStartIncluding": "6.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}