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TI-2025-15647 Aliases CVE-2025-21691GHSA-3m25-8xh3-c6p2

cachestat: fix page cache statistics permission checking

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: 15 fixed, 3 without a fix

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

Summary

In the Linux kernel, the following vulnerability has been resolved: cachestat: fix page cache statistics permission checking When the 'cachestat()' system call was added in commit cf264e1329fb ("cachestat: implement cachestat syscall"), it was meant to be a much more convenient (and performant) version of mincore() that didn't need mapping things into the user virtual address space in order to work. But it ended up missing the "check for writability or ownership" fix for mincore(), done in commit 134fca9063ad ("mm/mincore.c: make mincore() more conservative"). This just adds equivalent logic to 'cachestat()', modified for the file context (rather than vma).

Why it matters now

EPSS 0.00204 10th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.6.75, 6.12.12, 6.13.1 +1Red Hat: 3 advisoriesRed Hat: 15 fixed, 3 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.5 and later6.6.75, 6.12.12, 6.13.1, 6.14Patch availableCNA
  • Linux VendorLinux Affected 6.5 and later Fixed in 6.6.75, 6.12.12, 6.13.1, 6.14 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.5 to before 6.6.75; 6.7 to before 6.12.12VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.13:*:*:*:*:*:*:*6.13VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.5 to before 6.6.75; 6.7 to before 6.12.12 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.13:*:*:*:*:*:*:* Versions 6.13 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.6.75, 6.12.12, 6.13.1, 6.14

Red Hat 3 advisories

  • RHSA-2026:34094 Released 2026-07-01 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat CodeReady Linux Builder EUS (v.9.6) kernel-tools-libs-devel-5.14.0-570.125.1.el9_6, libperf-5.14.0-570.125.1.el9_6
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) kernel-64k-debug-devel-5.14.0-570.125.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.125.1.el9_6, kernel-64k-devel-5.14.0-570.125.1.el9_6 +12
    • Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel-5.14.0-570.125.1.el9_6, kernel-64k-5.14.0-570.125.1.el9_6, kernel-64k-core-5.14.0-570.125.1.el9_6 +28
    • Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt-5.14.0-570.125.1.el9_6, kernel-rt-64k-5.14.0-570.125.1.el9_6, kernel-rt-64k-core-5.14.0-570.125.1.el9_6 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt-5.14.0-570.125.1.el9_6, kernel-rt-core-5.14.0-570.125.1.el9_6, kernel-rt-debug-5.14.0-570.125.1.el9_6 +11
  • RHSA-2025:20518 Released 2025-11-11 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-611.5.1.el9_7, kernel-64k-debug-devel-matched-5.14.0-611.5.1.el9_7, kernel-64k-devel-5.14.0-611.5.1.el9_7 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-611.5.1.el9_7, kernel-64k-5.14.0-611.5.1.el9_7, kernel-64k-core-5.14.0-611.5.1.el9_7 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-611.5.1.el9_7, libperf-5.14.0-611.5.1.el9_7
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-611.5.1.el9_7, kernel-rt-64k-5.14.0-611.5.1.el9_7, kernel-rt-64k-core-5.14.0-611.5.1.el9_7 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-611.5.1.el9_7, kernel-rt-core-5.14.0-611.5.1.el9_7, kernel-rt-debug-5.14.0-611.5.1.el9_7 +9
  • RHSA-2025:20095 Released 2025-11-11 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-124.8.1.el10_1, kernel-64k-debug-devel-matched-6.12.0-124.8.1.el10_1, kernel-64k-devel-6.12.0-124.8.1.el10_1 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-124.8.1.el10_1, kernel-64k-6.12.0-124.8.1.el10_1, kernel-64k-core-6.12.0-124.8.1.el10_1 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-124.8.1.el10_1, libperf-6.12.0-124.8.1.el10_1
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-124.8.1.el10_1, kernel-rt-64k-6.12.0-124.8.1.el10_1, kernel-rt-64k-core-6.12.0-124.8.1.el10_1 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-124.8.1.el10_1, kernel-rt-core-6.12.0-124.8.1.el10_1, kernel-rt-debug-6.12.0-124.8.1.el10_1 +9

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 9AffectedNo fix yet
Red Hat CodeReady Linux Builder EUS (v.9.6)Fixed RHSA-2026:34094
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:34094
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux BaseOS EUS (v.9.6)Fixed RHSA-2026:34094
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux Real Time EUS (v.9.6)Fixed RHSA-2026:34094
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6)Fixed RHSA-2026:34094
Not affected: 1 product
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-21691
  2. 2026-10-03 Alias added: GHSA-3m25-8xh3-c6p2

References

Patch 4

  • 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