CVE-2021-47483
What it is
In the Linux kernel, the following vulnerability has been resolved: regmap: Fix possible double-free in regcache_rbtree_exit() In regcache_rbtree_insert_to_block(), when 'present' realloc failed, the 'blk' which is supposed to assign to 'rbnode->block' will be freed, so 'rbnode->block' points a freed memory, in the error handling path of regcache_rbtree_init(), 'rbnode->block' will be freed again in regcache_rbtree_exit(), KASAN will report double-free as follows: BUG: KASAN: double-free or invalid-free in kfree+0xce/0x390 Call Trace: slab_free_freelist_hook+0x10d/0x240 kfree+0xce/0x390 regcache_rbtree_exit+0x15d/0x1a0 regcache_rbtree_init+0x224/0x2c0 regcache_init+0x88d/0x1310 __regmap_init+0x3151/0x4a80 __devm_regmap_init+0x7d/0x100 madera_spi_probe+0x10f/0x333 [madera_spi] spi_probe+0x183/0x210 really_probe+0x285/0xc30 To fix this, moving up the assignment of rbnode->block to immediately after the reallocation has succeeded so that the data structure stays valid even if the second reallocation fails.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-415
- Record status
- Modified
Affected
- Linux Kernel < 4.4.291
- Linux Kernel < 4.9.289
- Linux Kernel < 4.14.254
- Linux Kernel < 4.19.215
- Linux Kernel < 5.4.157
- Linux Kernel < 5.10.77
- Linux Kernel < 5.14.16
- Linux Kernel 5.15
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2021-47483.md and follow it. Check whether this project is affected by CVE-2021-47483. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/1cead23c1c0bc766dacb900a3b0269f651ad596f
- https://git.kernel.org/stable/c/36e911a16b377bde0ad91a8c679069d0d310b1a6
- https://git.kernel.org/stable/c/3dae1a4eced3ee733d7222e69b8a55caf2d61091
- https://git.kernel.org/stable/c/50cc1462a668dc62949a1127388bc3af785ce047
- https://git.kernel.org/stable/c/55e6d8037805b3400096d621091dfbf713f97e83
- https://git.kernel.org/stable/c/758ced2c3878ff789801e6fee808e185c5cf08d6
- https://git.kernel.org/stable/c/e72dce9afbdbfa70d9b44f5908a50ff6c4858999
- https://git.kernel.org/stable/c/fc081477b47dfc3a6cb50a96087fc29674013fc2
- https://git.kernel.org/stable/c/1cead23c1c0bc766dacb900a3b0269f651ad596f
- https://git.kernel.org/stable/c/36e911a16b377bde0ad91a8c679069d0d310b1a6
References
- https://git.kernel.org/stable/c/1cead23c1c0bc766dacb900a3b0269f651ad596f
- https://git.kernel.org/stable/c/36e911a16b377bde0ad91a8c679069d0d310b1a6
- https://git.kernel.org/stable/c/3dae1a4eced3ee733d7222e69b8a55caf2d61091
- https://git.kernel.org/stable/c/50cc1462a668dc62949a1127388bc3af785ce047
- https://git.kernel.org/stable/c/55e6d8037805b3400096d621091dfbf713f97e83
- https://git.kernel.org/stable/c/758ced2c3878ff789801e6fee808e185c5cf08d6
- https://git.kernel.org/stable/c/e72dce9afbdbfa70d9b44f5908a50ff6c4858999
- https://git.kernel.org/stable/c/fc081477b47dfc3a6cb50a96087fc29674013fc2
- https://git.kernel.org/stable/c/1cead23c1c0bc766dacb900a3b0269f651ad596f
- https://git.kernel.org/stable/c/36e911a16b377bde0ad91a8c679069d0d310b1a6
- https://git.kernel.org/stable/c/3dae1a4eced3ee733d7222e69b8a55caf2d61091
- https://git.kernel.org/stable/c/50cc1462a668dc62949a1127388bc3af785ce047
- https://git.kernel.org/stable/c/55e6d8037805b3400096d621091dfbf713f97e83
- https://git.kernel.org/stable/c/758ced2c3878ff789801e6fee808e185c5cf08d6
- https://git.kernel.org/stable/c/e72dce9afbdbfa70d9b44f5908a50ff6c4858999
- https://git.kernel.org/stable/c/fc081477b47dfc3a6cb50a96087fc29674013fc2