CVE-2025-37958

Advisory lineage Upstream: 0 Downstream: 60
Analyzed
Published: 20 May 2025, 16:01
Last modified:11 May 2026, 21:18

Vulnerability Summary

Overall Risk (default)
low
22/100
CVSS Score
5.5 MEDIUM
v3.1 (nvd)
EPSS Score
0.12% LOW
0% probability +0.09%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

20 May 2025, 16:01
Published
Vulnerability first disclosed
11 May 2026, 21:18
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: mm/huge_memory: fix dereferencing invalid pmd migration entry When migrating a THP, concurrent access to the PMD migration entry during a deferred split scan can lead to an invalid address access, as illustrated below. To prevent this invalid access, it is necessary to check the PMD migration entry and return early. In this context, there is no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the equality of the target folio. Since the PMD migration entry is locked, it cannot be served as the target. Mailing list discussion and explanation from Hugh Dickins: "An anon_vma lookup points to a location which may contain the folio of interest, but might instead contain another folio: and weeding out those other folios is precisely what the "folio != pmd_folio((*pmd)" check (and the "risk of replacing the wrong folio" comment a few lines above it) is for." BUG: unable to handle page fault for address: ffffea60001db008 CPU: 0 UID: 0 PID: 2199114 Comm: tee Not tainted 6.14.0+ #4 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:split_huge_pmd_locked+0x3b5/0x2b60 Call Trace: <TASK> try_to_migrate_one+0x28c/0x3730 rmap_walk_anon+0x4f6/0x770 unmap_folio+0x196/0x1f0 split_huge_page_to_list_to_order+0x9f6/0x1560 deferred_split_scan+0xac5/0x12a0 shrinker_debugfs_scan_write+0x376/0x470 full_proxy_write+0x15c/0x220 vfs_write+0x2fc/0xcb0 ksys_write+0x146/0x250 do_syscall_64+0x6a/0x120 entry_SYSCALL_64_after_hwframe+0x76/0x7e The bug is found by syzkaller on an internal kernel, then confirmed on upstream.

CVSS Metrics

  • v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.12%• Percentile: 30%

Techniques & Countermeasures

  • CWE-476•NULL Pointer Dereference

    The product dereferences a pointer that it expects to be valid but is NULL.

Affected Systems

  • debian•debian_linux

    11.0

  • linux•linux

    ≥ 84c3fc4e9c563d8fb91cfdf5948da48fe1af34d3, < 753f142f7ff7d2223a47105b61e1efd91587d711 | ≥ 84c3fc4e9c563d8fb91cfdf5948da48fe1af34d3, < 9468afbda3fbfcec21ac8132364dff3dab945faf | ≥ 84c3fc4e9c563d8fb91cfdf5948da48fe1af34d3, < ef5706bed97e240b4abf4233ceb03da7336bc775 | ≥ 84c3fc4e9c563d8fb91cfdf5948da48fe1af34d3, < 22f6368768340260e862f35151d2e1c55cb1dc75 | ≥ 84c3fc4e9c563d8fb91cfdf5948da48fe1af34d3, < 3977946f61cdba87b6b5aaf7d7094e96089583a5 | ≥ 84c3fc4e9c563d8fb91cfdf5948da48fe1af34d3, < 6166c3cf405441f7147b322980144feb3cefc617 | ≥ 84c3fc4e9c563d8fb91cfdf5948da48fe1af34d3, < fbab262b0c8226c697af1851a424896ed47dedcc | ≥ 84c3fc4e9c563d8fb91cfdf5948da48fe1af34d3, < be6e843fc51a584672dfd9c4a6a24c8cb81d5fb7 | 4.14

  • linux•linux_kernel

    ≥ 4.14, < 5.4.295 | ≥ 5.5, < 5.10.239 | ≥ 5.11, < 5.15.186 | ≥ 5.16, < 6.1.142 | ≥ 6.2, < 6.6.95 | ≥ 6.7, < 6.12.29 | ≥ 6.13, < 6.14.7 | 6.15:rc1 | 6.15:rc2 | 6.15:rc3 | 6.15:rc4 | 6.15:rc5

References (10)