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TI-2024-24432 Aliases CVE-2024-36881

mm/userfaultfd: reset ptes when close() for wr-protected ones

Priority LOW 24Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 5 fixed, 3 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat.

Summary

In the Linux kernel, the following vulnerability has been resolved: mm/userfaultfd: reset ptes when close() for wr-protected ones Userfaultfd unregister includes a step to remove wr-protect bits from all the relevant pgtable entries, but that only covered an explicit UFFDIO_UNREGISTER ioctl, not a close() on the userfaultfd itself. Cover that too. This fixes a WARN trace. The only user visible side effect is the user can observe leftover wr-protect bits even if the user close()ed on an userfaultfd when releasing the last reference of it. However hopefully that should be harmless, and nothing bad should happen even if so. This change is now more important after the recent page-table-check patch we merged in mm-unstable (446dd9ad37d0 ("mm/page_table_check: support userfault wr-protect entries")), as we'll do sanity check on uffd-wp bits without vma context. So it's better if we can 100% guarantee no uffd-wp bit leftovers, to make sure each report will be valid.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00239 15th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.20, 6.1.191, 6.6.31 +2Red Hat: 1 advisoryRed Hat: 5 fixed, 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.19.6 to before 5.205.20Patch availableCNA
LinuxLinux6.0 and later6.1.191, 6.6.31, 6.8.10, 6.9Patch availableCNA
  • Linux VendorLinux Affected 5.19.6 to before 5.20 Fixed in 5.20 Patch available CNA
  • Linux VendorLinux Affected 6.0 and later Fixed in 6.1.191, 6.6.31, 6.8.10, 6.9 Patch available CNA

CPE configurations NVD · 8

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.19.6 to before 6.6.31; 6.7 to before 6.8.10VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.9:rc1:*:*:*:*:*:*6.9 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.9:rc2:*:*:*:*:*:*6.9 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.9:rc3:*:*:*:*:*:*6.9 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.9:rc4:*:*:*:*:*:*6.9 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.9:rc5:*:*:*:*:*:*6.9 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.9:rc6:*:*:*:*:*:*6.9 rc6VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.9:rc7:*:*:*:*:*:*6.9 rc7VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.19.6 to before 6.6.31; 6.7 to before 6.8.10 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.9:rc1:*:*:*:*:*:* Versions 6.9 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.9:rc2:*:*:*:*:*:* Versions 6.9 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.9:rc3:*:*:*:*:*:* Versions 6.9 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.9:rc4:*:*:*:*:*:* Versions 6.9 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.9:rc5:*:*:*:*:*:* Versions 6.9 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.9:rc6:*:*:*:*:*:* Versions 6.9 rc6 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.9:rc7:*:*:*:*:*:* Versions 6.9 rc7 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.20
  • Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.31, 6.8.10, 6.9

Red Hat 1 advisory

  • RHSA-2024:9315 Released 2024-11-12 · Red Hat rating Moderate
    kernel security update
    • Red Hat CodeReady Linux Builder (v. 9) kernel-cross-headers-5.14.0-503.11.1.el9_5, kernel-tools-libs-devel-5.14.0-503.11.1.el9_5, libperf-5.14.0-503.11.1.el9_5
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-503.11.1.el9_5, kernel-64k-debug-devel-matched-5.14.0-503.11.1.el9_5, kernel-64k-devel-5.14.0-503.11.1.el9_5 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) bpftool-7.4.0-503.11.1.el9_5, kernel-5.14.0-503.11.1.el9_5, kernel-64k-5.14.0-503.11.1.el9_5 +30
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-503.11.1.el9_5, kernel-rt-core-5.14.0-503.11.1.el9_5, kernel-rt-debug-5.14.0-503.11.1.el9_5 +9
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-503.11.1.el9_5, kernel-rt-core-5.14.0-503.11.1.el9_5, kernel-rt-debug-5.14.0-503.11.1.el9_5 +11

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 8AffectedNo fix yet
Red Hat CodeReady Linux Builder (v. 9)Fixed RHSA-2024:9315
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2024:9315
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2024:9315
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2024:9315
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2024:9315
Not affected: 3 products
  • Red Hat CodeReady Linux Builder (v. 9)
  • Red Hat Enterprise Linux 9
  • Red Hat Enterprise Linux AppStream (v. 9)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-36881
  2. 2026-10-29 Affected versions changed · Red Hat
  3. 2026-10-30 Fix available: Linux/Linux@1da0471de653b13c8f63dcd32a23574d683c8310, Linux/[email protected] · CNA
  4. 2026-10-30 1 new reference · CNA

References

Patch 3

Other 1

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences