CVE-2021-47321

2024-05-2115:15:19

416baaa9-dc9f-4396-8d5f-8c081fb06d67

web.nvd.nist.gov

linux kernel

use-after-free

watchdog driver

vulnerability

fix

del_timer_sync

nvd

6.6 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

13.2%

JSON

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

watchdog: Fix possible use-after-free by calling del_timer_sync()

This driver’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.

Affected configurations

Vulners

Node

linuxlinux_kernelRange4.4.0–4.4.276

linuxlinux_kernelRange4.5.0–4.9.276

linuxlinux_kernelRange4.10.0–4.14.240

linuxlinux_kernelRange4.15.0–4.19.198

linuxlinux_kernelRange4.20.0–5.4.134

linuxlinux_kernelRange5.5.0–5.10.52

linuxlinux_kernelRange5.11.0–5.12.19

linuxlinux_kernelRange5.13.0–5.13.4

linuxlinux_kernelRange5.14.0≥

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/watchdog/lpc18xx_wdt.c",
      "drivers/watchdog/w83877f_wdt.c"
    ],
    "versions": [
      {
        "version": "1da177e4c3f4",
        "lessThan": "58606882ad8e",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "ca96b8ea5e74",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "8bec568d7518",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "ecd620e0fb1f",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "db222f1477ad",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "66ba9cf929b1",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "4c05dac488a6",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "1a053c4d7168",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "d0212f095ab5",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/watchdog/lpc18xx_wdt.c",
      "drivers/watchdog/w83877f_wdt.c"
    ],
    "versions": [
      {
        "version": "4.4.276",
        "lessThanOrEqual": "4.4.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.9.276",
        "lessThanOrEqual": "4.9.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.14.240",
        "lessThanOrEqual": "4.14.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.19.198",
        "lessThanOrEqual": "4.19.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.4.134",
        "lessThanOrEqual": "5.4.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.52",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.12.19",
        "lessThanOrEqual": "5.12.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.13.4",
        "lessThanOrEqual": "5.13.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.14",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]