CVE-2021-47090: mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page()
Vulnerability summary
CVE-2021-47090 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.35% chance of exploitation in the next 30 days, higher than 28.9% of scored vulnerabilities. 3 public exploits are recorded.
Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 1Timeline
- 04-03-2024PublishedVulnerability first disclosed.
- 11-05-2026Last modifiedVulnerability information updated.
Description
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
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.35%
Chance of exploitation in the next 30 days
Percentile
29%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.35% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
3 foundExploit Reference (git.kernel.org)
Maturity: unknown
Exploit Reference (git.kernel.org)
Maturity: unknown
Exploit Reference (git.kernel.org)
Maturity: unknown
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu62 products
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
- linux-aws-5.13All versions (No fix recorded)
- linux-aws-5.19All versions (No fix recorded)
Linux2 products
- linux≥ b94e02822debdf0cc473556aad7dcc859f216653, < 1f207076740101fed87074a6bc924dbe806f08a5 | ≥ b94e02822debdf0cc473556aad7dcc859f216653, < c691e7575eff76e563b0199c23ec46bd454f43e3 | ≥ b94e02822debdf0cc473556aad7dcc859f216653, < 2a57d83c78f889bf3f54eede908d0643c40d5418 | 5.10
- linux_kernel≥ 5.10, < 5.10.89 | ≥ 5.11, < 5.15.12 | 5.16:rc1 | 5.16:rc2 | 5.16:rc3 | 5.16:rc4 | 5.16:rc5 | 5.16:rc6
Debian1 product
- linux< 5.15.15-1
3 vendors · 65 products