Описание
In the Linux kernel, the following vulnerability has been resolved:
wireguard: netlink: check for dangling peer via is_dead instead of empty list
If all peers are removed via wg_peer_remove_all(), rather than setting
peer_list to empty, the peer is added to a temporary list with a head on
the stack of wg_peer_remove_all(). If a netlink dump is resumed and the
cursored peer is one that has been removed via wg_peer_remove_all(), it
will iterate from that peer and then attempt to dump freed peers.
Fix this by instead checking peer->is_dead, which was explictly created
for this purpose. Also move up the device_update_lock lockdep assertion,
since reading is_dead relies on that.
It can be reproduced by a small script like:
echo "Setting config..."
ip link add dev wg0 type wireguard
wg setconf wg0 /big-config
(
while true; do
echo "Showing config..."
wg showconf wg0 > /dev/null
done
) &
sleep 4
wg setconf wg0 <(printf "[Peer]\nPublicKey=$(wg genkey)\n")
Resulting in:
BUG: KASAN: slab-use-after-free in __lock_acquire+0x182a/0x1b20
Read of size 8 at addr ffff88811956ec70 by task wg/59
CPU: 2 PID: 59 Comm: wg Not tainted 6.8.0-rc2-debug+ #5
Call Trace:
dump_stack_lvl+0x47/0x70
print_address_description.constprop.0+0x2c/0x380
print_report+0xab/0x250
kasan_report+0xba/0xf0
__lock_acquire+0x182a/0x1b20
lock_acquire+0x191/0x4b0
down_read+0x80/0x440
get_peer+0x140/0xcb0
wg_get_device_dump+0x471/0x1130
A flaw was found in the Linux kernel's WireGuard component. A local user could trigger a use-after-free vulnerability when retrieving configuration data while network peers are concurrently removed. This flaw can lead to a Denial of Service (DoS) through a kernel crash or potentially enable local privilege escalation.
Отчет
This vulnerability is rated as Low impact because WireGuard is not enabled or configured by default on Red Hat Enterprise Linux, and exploitation requires an active WireGuard interface with dynamic peer configuration. To trigger the race condition, a local user must time netlink status queries precisely during peer removal operations. Although the resulting memory corruption can cause a kernel crash, the specific operational setup and timing window significantly reduce practical risk in standard deployments.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat Enterprise Linux 6 | kernel | Not affected | ||
| Red Hat Enterprise Linux 7 | kernel | Not affected | ||
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | ||
| Red Hat Enterprise Linux 8 | kernel | Not affected | ||
| Red Hat Enterprise Linux 8 | kernel-rt | Not affected | ||
| Red Hat Enterprise Linux 9 | kernel-rt | Affected | ||
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2024:9315 | 12.11.2024 |
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2024:9315 | 12.11.2024 |
Показывать по
Дополнительная информация
Статус:
5.5 Medium
CVSS3
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: wireguard: netlink: check for dangling peer via is_dead instead of empty list If all peers are removed via wg_peer_remove_all(), rather than setting peer_list to empty, the peer is added to a temporary list with a head on the stack of wg_peer_remove_all(). If a netlink dump is resumed and the cursored peer is one that has been removed via wg_peer_remove_all(), it will iterate from that peer and then attempt to dump freed peers. Fix this by instead checking peer->is_dead, which was explictly created for this purpose. Also move up the device_update_lock lockdep assertion, since reading is_dead relies on that. It can be reproduced by a small script like: echo "Setting config..." ip link add dev wg0 type wireguard wg setconf wg0 /big-config ( while true; do echo "Showing config..." wg showconf wg0 > /dev/null done ) & sleep 4 wg setconf wg0 <(printf "[Peer]\nPublicKey=$(wg genkey)\n") Resulting in: BUG: KASAN: slab-use-...
In the Linux kernel, the following vulnerability has been resolved: wireguard: netlink: check for dangling peer via is_dead instead of empty list If all peers are removed via wg_peer_remove_all(), rather than setting peer_list to empty, the peer is added to a temporary list with a head on the stack of wg_peer_remove_all(). If a netlink dump is resumed and the cursored peer is one that has been removed via wg_peer_remove_all(), it will iterate from that peer and then attempt to dump freed peers. Fix this by instead checking peer->is_dead, which was explictly created for this purpose. Also move up the device_update_lock lockdep assertion, since reading is_dead relies on that. It can be reproduced by a small script like: echo "Setting config..." ip link add dev wg0 type wireguard wg setconf wg0 /big-config ( while true; do echo "Showing config..." wg showconf wg0 > /dev/null done ) & sleep 4 w
In the Linux kernel, the following vulnerability has been resolved: w ...
In the Linux kernel, the following vulnerability has been resolved: wireguard: netlink: check for dangling peer via is_dead instead of empty list If all peers are removed via wg_peer_remove_all(), rather than setting peer_list to empty, the peer is added to a temporary list with a head on the stack of wg_peer_remove_all(). If a netlink dump is resumed and the cursored peer is one that has been removed via wg_peer_remove_all(), it will iterate from that peer and then attempt to dump freed peers. Fix this by instead checking peer->is_dead, which was explictly created for this purpose. Also move up the device_update_lock lockdep assertion, since reading is_dead relies on that. It can be reproduced by a small script like: echo "Setting config..." ip link add dev wg0 type wireguard wg setconf wg0 /big-config ( while true; do echo "Showing config..." wg showconf wg0 > /dev/null done ) & sleep 4 ...
5.5 Medium
CVSS3