CVE-2026-23437

In the Linux kernel, the following vulnerability has been resolved: net: shaper: protect late read accesses to the hierarchy We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections. This is not proper, a conversion from a ref to a locked netdev must include a liveness check (a check if the netdev hasn't been unregistered already). Fix the read cases (those under RCU). Writes needs a separate change to protect from creating the hierarchy after flush has already run.

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/0f9ea7141f365b4f27226898e62220fb98ef8dc6	Patch
https://git.kernel.org/stable/c/348758ba74e6a348299965b16a97cfb817545cc0	Patch
https://git.kernel.org/stable/c/581eee0890a8bde44f1fb78ad3e70502a897d583	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:6.13:-::::::
	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::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc4::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc5::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc6::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc7::::::

History

No history.

Information

Published : 2026-04-03 16:16

Updated : 2026-07-24 21:10

NVD link : CVE-2026-23437

Mitre link : CVE-2026-23437

CVE.ORG link : CVE-2026-23437

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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Then later in the body of the callback\nwe take its lock or RCU which are the actual protections.\n\nThis is not proper, a conversion from a ref to a locked netdev\nmust include a liveness check (a check if the netdev hasn't been\nunregistered already). Fix the read cases (those under RCU).\nWrites needs a separate change to protect from creating the\nhierarchy after flush has already run."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet: shaper: proteger los accesos de lectura tard\u00edos a la jerarqu\u00eda\n\nBuscamos un netdev durante la preparaci\u00f3n de las operaciones de Netlink (pre-callbacks) y tomamos una referencia a \u00e9l. Luego, m\u00e1s tarde, en el cuerpo del callback, tomamos su bloqueo o RCU, que son las protecciones reales.\n\nEsto no es adecuado; una conversi\u00f3n de una referencia a un netdev bloqueado debe incluir una comprobaci\u00f3n de actividad (una comprobaci\u00f3n de si el netdev no ha sido ya desregistrado). Corregir los casos de lectura (aquellos bajo RCU). Las escrituras necesitan un cambio separado para proteger de la creaci\u00f3n de la jerarqu\u00eda despu\u00e9s de que el vaciado ya se haya ejecutado."}], "lastModified": "2026-07-24T21:10:00.143", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A2A94618-E3D4-4741-B60F-78501912CE89", "versionEndExcluding": "6.18.20", "versionStartIncluding": "6.13.1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "96D34333-38BE-4414-9E79-6EB764329581", "versionEndExcluding": "6.19.10", "versionStartIncluding": "6.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:-:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5A3F9505-6B98-4269-8B81-127E55A1BF00"}, {"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"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}