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fstec логотип

BDU:2025-07464

Опубликовано: 30 сент. 2021
Источник: fstec
CVSS3: 7.8
CVSS2: 6.8
EPSS Низкий

Описание

Уязвимость функции fl_walk() модуля net/sched/cls_flower.c подсистемы управления трафиком net/sched ядра операционной системы Linux связана с повторным использованием ранее освобожденной памяти. Эксплуатация уязвимости может позволить нарушителю оказать воздействие на конфиденциальность, целостность и доступность защищаемой информации.

Вендор

Сообщество свободного программного обеспечения

Наименование ПО

Linux

Версия ПО

от 5.5 до 5.10.70 включительно (Linux)
от 5.11 до 5.14.9 включительно (Linux)
от 5.3 до 5.4.150 включительно (Linux)

Тип ПО

Операционная система

Операционные системы и аппаратные платформы

Сообщество свободного программного обеспечения Linux от 5.5 до 5.10.70 включительно
Сообщество свободного программного обеспечения Linux от 5.11 до 5.14.9 включительно
Сообщество свободного программного обеспечения Linux от 5.3 до 5.4.150 включительно

Уровень опасности уязвимости

Средний уровень опасности (базовая оценка CVSS 2.0 составляет 6,8)
Высокий уровень опасности (базовая оценка CVSS 3.1 составляет 7,8)

Возможные меры по устранению уязвимости

В условиях отсутствия обновлений безопасности от производителя рекомендуется придерживаться "Рекомендаций по безопасной настройке операционных систем LINUX", изложенных в методическом документе ФСТЭК России, утверждённом 25 декабря 2022 года.
Использование рекомендаций:
Для Linux:
https://lore.kernel.org/linux-cve-announce/2024052149-CVE-2021-47402-6c19@gregkh/
https://git.kernel.org/linus/d5ef190693a7d76c5c192d108e8dec48307b46ee
https://git.linuxtesting.ru/pub/scm/linux/kernel/git/lvc/linux-stable.git/commit/?h=v5.10.176-lvc1&id=d0d520c19e7ea19ed38dc5797b12397b6ccf9f88
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.151
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.71
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.14.10
https://git.kernel.org/stable/c/694b0cee7f8546b69a80996a29cb3cf4149c0453
https://git.kernel.org/stable/c/dab4677bdbffa5c8270e79e34e51c89efa0728a0
https://git.kernel.org/stable/c/d0d520c19e7ea19ed38dc5797b12397b6ccf9f88
https://git.kernel.org/stable/c/d5ef190693a7d76c5c192d108e8dec48307b46ee

Статус уязвимости

Подтверждена производителем

Наличие эксплойта

Данные уточняются

Информация об устранении

Уязвимость устранена

Идентификаторы других систем описаний уязвимостей

EPSS

Процентиль: 1%
0.00013
Низкий

7.8 High

CVSS3

6.8 Medium

CVSS2

Связанные уязвимости

CVSS3: 7.8
ubuntu
около 1 года назад

In the Linux kernel, the following vulnerability has been resolved: net: sched: flower: protect fl_walk() with rcu Patch that refactored fl_walk() to use idr_for_each_entry_continue_ul() also removed rcu protection of individual filters which causes following use-after-free when filter is deleted concurrently. Fix fl_walk() to obtain rcu read lock while iterating and taking the filter reference and temporary release the lock while calling arg->fn() callback that can sleep. KASAN trace: [ 352.773640] ================================================================== [ 352.775041] BUG: KASAN: use-after-free in fl_walk+0x159/0x240 [cls_flower] [ 352.776304] Read of size 4 at addr ffff8881c8251480 by task tc/2987 [ 352.777862] CPU: 3 PID: 2987 Comm: tc Not tainted 5.15.0-rc2+ #2 [ 352.778980] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 352.781022] Call Trace: [ 352.781573] dump_stack_lvl+0x46/0x5a [ 352.7823...

CVSS3: 7
redhat
около 1 года назад

In the Linux kernel, the following vulnerability has been resolved: net: sched: flower: protect fl_walk() with rcu Patch that refactored fl_walk() to use idr_for_each_entry_continue_ul() also removed rcu protection of individual filters which causes following use-after-free when filter is deleted concurrently. Fix fl_walk() to obtain rcu read lock while iterating and taking the filter reference and temporary release the lock while calling arg->fn() callback that can sleep. KASAN trace: [ 352.773640] ================================================================== [ 352.775041] BUG: KASAN: use-after-free in fl_walk+0x159/0x240 [cls_flower] [ 352.776304] Read of size 4 at addr ffff8881c8251480 by task tc/2987 [ 352.777862] CPU: 3 PID: 2987 Comm: tc Not tainted 5.15.0-rc2+ #2 [ 352.778980] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 352.781022] Call Trace: [ 352.781573] dump_stack_lvl+0x46/0x5a [ 352.7823...

CVSS3: 7.8
nvd
около 1 года назад

In the Linux kernel, the following vulnerability has been resolved: net: sched: flower: protect fl_walk() with rcu Patch that refactored fl_walk() to use idr_for_each_entry_continue_ul() also removed rcu protection of individual filters which causes following use-after-free when filter is deleted concurrently. Fix fl_walk() to obtain rcu read lock while iterating and taking the filter reference and temporary release the lock while calling arg->fn() callback that can sleep. KASAN trace: [ 352.773640] ================================================================== [ 352.775041] BUG: KASAN: use-after-free in fl_walk+0x159/0x240 [cls_flower] [ 352.776304] Read of size 4 at addr ffff8881c8251480 by task tc/2987 [ 352.777862] CPU: 3 PID: 2987 Comm: tc Not tainted 5.15.0-rc2+ #2 [ 352.778980] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 352.781022] Call Trace: [ 352.781573] dump_stack_lvl+0x46/0x5a [ 352.78

CVSS3: 7.8
debian
около 1 года назад

In the Linux kernel, the following vulnerability has been resolved: n ...

CVSS3: 7.8
github
около 1 года назад

In the Linux kernel, the following vulnerability has been resolved: net: sched: flower: protect fl_walk() with rcu Patch that refactored fl_walk() to use idr_for_each_entry_continue_ul() also removed rcu protection of individual filters which causes following use-after-free when filter is deleted concurrently. Fix fl_walk() to obtain rcu read lock while iterating and taking the filter reference and temporary release the lock while calling arg->fn() callback that can sleep. KASAN trace: [ 352.773640] ================================================================== [ 352.775041] BUG: KASAN: use-after-free in fl_walk+0x159/0x240 [cls_flower] [ 352.776304] Read of size 4 at addr ffff8881c8251480 by task tc/2987 [ 352.777862] CPU: 3 PID: 2987 Comm: tc Not tainted 5.15.0-rc2+ #2 [ 352.778980] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 352.781022] Call Trace: [ 352.781573] dump_stack_lvl+0x46/0x5a [ 352...

EPSS

Процентиль: 1%
0.00013
Низкий

7.8 High

CVSS3

6.8 Medium

CVSS2