CVE-2021-47090
What it is
In the Linux kernel, the following vulnerability has been resolved: mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page() Hulk Robot reported a panic in put_page_testzero() when testing madvise() with MADV_SOFT_OFFLINE. The BUG() is triggered when retrying get_any_page(). This is because we keep MF_COUNT_INCREASED flag in second try but the refcnt is not increased. page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0) ------------[ cut here ]------------ kernel BUG at include/linux/mm.h:737! invalid opcode: 0000 [#1] PREEMPT SMP CPU: 5 PID: 2135 Comm: sshd Tainted: G B 5.16.0-rc6-dirty #373 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: release_pages+0x53f/0x840 Call Trace: free_pages_and_swap_cache+0x64/0x80 tlb_flush_mmu+0x6f/0x220 unmap_page_range+0xe6c/0x12c0 unmap_single_vma+0x90/0x170 unmap_vmas+0xc4/0x180 exit_mmap+0xde/0x3a0 mmput+0xa3/0x250 do_exit+0x564/0x1470 do_group_exit+0x3b/0x100 __do_sys_exit_group+0x13/0x20 __x64_sys_exit_group+0x16/0x20 do_syscall_64+0x34/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Modules linked in: ---[ end trace e99579b570fe0649 ]--- RIP: 0010:release_pages+0x53f/0x840
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.4% 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: 0.4% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Record status
- Analyzed
Affected
- Linux Kernel < 5.10.89
- Linux Kernel < 5.15.12
- Linux Kernel 5.16
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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-2021-47090.md and follow it. Check whether this project is affected by CVE-2021-47090. 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/1f207076740101fed87074a6bc924dbe806f08a5
- https://git.kernel.org/stable/c/2a57d83c78f889bf3f54eede908d0643c40d5418
- https://git.kernel.org/stable/c/c691e7575eff76e563b0199c23ec46bd454f43e3
- https://git.kernel.org/stable/c/1f207076740101fed87074a6bc924dbe806f08a5
- https://git.kernel.org/stable/c/2a57d83c78f889bf3f54eede908d0643c40d5418
- https://git.kernel.org/stable/c/c691e7575eff76e563b0199c23ec46bd454f43e3
References
- https://git.kernel.org/stable/c/1f207076740101fed87074a6bc924dbe806f08a5
- https://git.kernel.org/stable/c/2a57d83c78f889bf3f54eede908d0643c40d5418
- https://git.kernel.org/stable/c/c691e7575eff76e563b0199c23ec46bd454f43e3
- https://git.kernel.org/stable/c/1f207076740101fed87074a6bc924dbe806f08a5
- https://git.kernel.org/stable/c/2a57d83c78f889bf3f54eede908d0643c40d5418
- https://git.kernel.org/stable/c/c691e7575eff76e563b0199c23ec46bd454f43e3