CVE-2021-47324
In the Linux kernel, the following vulnerability has been resolved: watchdog: Fix possible use-after-free in wdt_startup() This module's remove path calls del_timer().
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.16%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: watchdog: Fix possible use-after-free in wdt_startup() This module's remove path calls del_timer(). However, that function does not wait until the timer handler finishes. This means that the timer handler may still be running after the driver's remove function has finished, which would result in a use-after-free. Fix by calling del_timer_sync(), which makes sure the timer handler has finished, and unable to re-schedule itself.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.16% probability · 65th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-416
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/0ac50a76cf3cd63db000648b3b19f3f98b8aaa76Patch
- https://git.kernel.org/stable/c/146cc288fb80c662c9c35e7bc58325d1ac0a7875Patch
- https://git.kernel.org/stable/c/63a3dc24bd053792f84cb4eef0168b1266202a02Patch
- https://git.kernel.org/stable/c/862f2b5a7c38762ac9e369daefbf361a91aca685Patch
- https://git.kernel.org/stable/c/8adbbe6c86bb13e14f8a19e036ae5f4f5661fd90Patch
- https://git.kernel.org/stable/c/a397cb4576fc2fc802562418b3a50b8f67d60d31Patch
- https://git.kernel.org/stable/c/b4ebf4a4692e84163a69444c70ad515de06e2259Patch
- https://git.kernel.org/stable/c/c08a6b31e4917034f0ed0cb457c3bb209576f542Patch
- https://git.kernel.org/stable/c/dc9403097be52d57a5c9c35efa9be79d166a78afPatch
- https://git.kernel.org/stable/c/0ac50a76cf3cd63db000648b3b19f3f98b8aaa76Patch
- https://git.kernel.org/stable/c/146cc288fb80c662c9c35e7bc58325d1ac0a7875Patch
- https://git.kernel.org/stable/c/63a3dc24bd053792f84cb4eef0168b1266202a02Patch
- https://git.kernel.org/stable/c/862f2b5a7c38762ac9e369daefbf361a91aca685Patch
- https://git.kernel.org/stable/c/8adbbe6c86bb13e14f8a19e036ae5f4f5661fd90Patch
- https://git.kernel.org/stable/c/a397cb4576fc2fc802562418b3a50b8f67d60d31Patch
- https://git.kernel.org/stable/c/b4ebf4a4692e84163a69444c70ad515de06e2259Patch
- https://git.kernel.org/stable/c/c08a6b31e4917034f0ed0cb457c3bb209576f542Patch
- https://git.kernel.org/stable/c/dc9403097be52d57a5c9c35efa9be79d166a78afPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.