CVE-2024-42233 — LOW (3.3) — White Hats Nepal

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: filemap: replace pte_offset_map() with pte_offset_map_nolock() The vmf->ptl in filemap_fault_recheck_pte_none() is still set from handle_pte_fault(). But at the same time, we did a pte_unmap(vmf->pte). After a pte_unmap(vmf->pte) unmap and rcu_read_unlock(), the page table may be racily changed and vmf->ptl maybe fails to protect the actual page table. Fix this by replacing pte_offset_map() with pte_offset_map_nolock(). As David said, the PTL pointer might be stale so if we continue to use it infilemap_fault_recheck_pte_none(), it might trigger UAF. Also, if the PTL fails, the issue fixed by commit 58f327f2ce80 ("filemap: avoid unnecessary major faults in filemap_fault()") might reappear.

CVSS Score

3.3

LOW

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

LOW

Availability

NONE

Affected Products

Vendor	Product	Versions
Linux	Linux Kernel	>= 6.9, < 6.9.10

References

FAQ

What is CVE-2024-42233?

CVE-2024-42233 is a vulnerability with a CVSS score of 3.3 (LOW). In the Linux kernel, the following vulnerability has been resolved: filemap: replace pte_offset_map() with pte_offset_map_nolock() The vmf->ptl in filemap_fault_recheck_pte_none() is still set from ...

How severe is CVE-2024-42233?

CVE-2024-42233 has been rated LOW with a CVSS base score of 3.3/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2024-42233?

Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.