Read the docs
TI-2025-26828 Aliases CVE-2025-40158GHSA-4g43-pmw7-v27w

ipv6: use RCU in ip6_output()

Priority LOW 36Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 38 fixed, 1 without a fix

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

Summary

In the Linux kernel, the following vulnerability has been resolved: ipv6: use RCU in ip6_output() Use RCU in ip6_output() in order to use dst_dev_rcu() to prevent possible UAF. We can remove rcu_read_lock()/rcu_read_unlock() pairs from ip6_finish_output2().

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00555 46th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.1.191, 6.6.160, 6.12.113 +2Red Hat: 12 advisoriesRed Hat: 38 fixed, 1 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
LinuxLinux4.13 and later6.1.191, 6.6.160, 6.12.113, 6.17.3, 6.18Patch availableCNA
  • Linux VendorLinux Affected 4.13 and later Fixed in 6.1.191, 6.6.160, 6.12.113, 6.17.3, 6.18 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.160, 6.12.113, 6.17.3, 6.18

Red Hat 12 advisories

  • RHSA-2026:27731 Released 2026-06-22 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) kernel-64k-debug-devel-6.12.0-55.82.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.82.1.el10_0, kernel-64k-devel-6.12.0-55.82.1.el10_0 +12
    • Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel-6.12.0-55.82.1.el10_0, kernel-64k-6.12.0-55.82.1.el10_0, kernel-64k-core-6.12.0-55.82.1.el10_0 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) kernel-tools-libs-devel-6.12.0-55.82.1.el10_0, libperf-6.12.0-55.82.1.el10_0
    • Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt-6.12.0-55.82.1.el10_0, kernel-rt-64k-6.12.0-55.82.1.el10_0, kernel-rt-64k-core-6.12.0-55.82.1.el10_0 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) kernel-rt-6.12.0-55.82.1.el10_0, kernel-rt-core-6.12.0-55.82.1.el10_0, kernel-rt-debug-6.12.0-55.82.1.el10_0 +11
  • RHSA-2026:26535 Released 2026-06-17 · Red Hat rating Critical
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux BaseOS AUS (v.8.4) bpftool-4.18.0-305.194.1.el8_4, kernel-4.18.0-305.194.1.el8_4, kernel-abi-stablelists-4.18.0-305.194.1.el8_4 +14
    • Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4) bpftool-4.18.0-305.194.1.el8_4, kernel-4.18.0-305.194.1.el8_4, kernel-abi-stablelists-4.18.0-305.194.1.el8_4 +14
  • RHSA-2026:26515 Released 2026-06-17 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) kernel-64k-debug-devel-5.14.0-284.176.1.el9_2, kernel-64k-debug-devel-matched-5.14.0-284.176.1.el9_2, kernel-64k-devel-5.14.0-284.176.1.el9_2 +10
    • Red Hat Enterprise Linux BaseOS E4S (v.9.2) bpftool-7.0.0-284.176.1.el9_2, kernel-5.14.0-284.176.1.el9_2, kernel-64k-5.14.0-284.176.1.el9_2 +29
Show 9 more Red Hat advisories
  • RHSA-2026:26462 Released 2026-06-17 · Red Hat rating Important
    kernel-rt security update
    • Red Hat Enterprise Linux Real Time E4S (v.9.2) kernel-rt-5.14.0-284.176.1.rt14.461.el9_2, kernel-rt-core-5.14.0-284.176.1.rt14.461.el9_2, kernel-rt-debug-5.14.0-284.176.1.rt14.461.el9_2 +9
    • Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) kernel-rt-5.14.0-284.176.1.rt14.461.el9_2, kernel-rt-core-5.14.0-284.176.1.rt14.461.el9_2, kernel-rt-debug-5.14.0-284.176.1.rt14.461.el9_2 +11
  • RHSA-2026:25533 Released 2026-06-12 · Red Hat rating Critical
    kernel security update
    • Red Hat Enterprise Linux BaseOS AUS (v.8.6) bpftool-4.18.0-372.195.1.el8_6, kernel-4.18.0-372.195.1.el8_6, kernel-abi-stablelists-4.18.0-372.195.1.el8_6 +14
    • Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6) bpftool-4.18.0-372.195.1.el8_6, kernel-4.18.0-372.195.1.el8_6, kernel-abi-stablelists-4.18.0-372.195.1.el8_6 +14
  • RHSA-2026:25218 Released 2026-06-11 · Red Hat rating Important
    kernel security update
    • Red Hat CodeReady Linux Builder EUS (v.9.6) kernel-tools-libs-devel-5.14.0-570.120.1.el9_6, libperf-5.14.0-570.120.1.el9_6
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) kernel-64k-debug-devel-5.14.0-570.120.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.120.1.el9_6, kernel-64k-devel-5.14.0-570.120.1.el9_6 +12
    • Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel-5.14.0-570.120.1.el9_6, kernel-64k-5.14.0-570.120.1.el9_6, kernel-64k-core-5.14.0-570.120.1.el9_6 +28
    • Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt-5.14.0-570.120.1.el9_6, kernel-rt-64k-5.14.0-570.120.1.el9_6, kernel-rt-64k-core-5.14.0-570.120.1.el9_6 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt-5.14.0-570.120.1.el9_6, kernel-rt-core-5.14.0-570.120.1.el9_6, kernel-rt-debug-5.14.0-570.120.1.el9_6 +11
  • RHSA-2026:22964 Released 2026-06-04 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux BaseOS E4S (v.8.8) bpftool-4.18.0-477.145.1.el8_8, kernel-4.18.0-477.145.1.el8_8, kernel-abi-stablelists-4.18.0-477.145.1.el8_8 +14
    • Red Hat Enterprise Linux BaseOS TUS (v.8.8) bpftool-4.18.0-477.145.1.el8_8, kernel-4.18.0-477.145.1.el8_8, kernel-abi-stablelists-4.18.0-477.145.1.el8_8 +14
  • RHSA-2026:23237 Released 2026-06-04 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) kernel-64k-debug-devel-5.14.0-427.129.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.129.1.el9_4, kernel-64k-devel-5.14.0-427.129.1.el9_4 +11
    • Red Hat Enterprise Linux BaseOS E4S (v.9.4) bpftool-7.3.0-427.129.1.el9_4, kernel-5.14.0-427.129.1.el9_4, kernel-64k-5.14.0-427.129.1.el9_4 +29
    • Red Hat Enterprise Linux Real Time E4S (v.9.4) kernel-rt-5.14.0-427.129.1.el9_4, kernel-rt-core-5.14.0-427.129.1.el9_4, kernel-rt-debug-5.14.0-427.129.1.el9_4 +9
    • Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4) kernel-rt-5.14.0-427.129.1.el9_4, kernel-rt-core-5.14.0-427.129.1.el9_4, kernel-rt-debug-5.14.0-427.129.1.el9_4 +11
  • RHSA-2026:2378 Released 2026-02-10 · Red Hat rating Moderate
    kernel-rt security update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-553.104.1.rt7.445.el8_10, kernel-rt-core-4.18.0-553.104.1.rt7.445.el8_10, kernel-rt-debug-4.18.0-553.104.1.rt7.445.el8_10 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-553.104.1.rt7.445.el8_10, kernel-rt-core-4.18.0-553.104.1.rt7.445.el8_10, kernel-rt-debug-4.18.0-553.104.1.rt7.445.el8_10 +7
  • RHSA-2026:2264 Released 2026-02-09 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.104.1.el8_10, kernel-4.18.0-553.104.1.el8_10, kernel-abi-stablelists-4.18.0-553.104.1.el8_10 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.104.1.el8_10
  • RHSA-2026:2212 Released 2026-02-09 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-611.30.1.el9_7, kernel-64k-debug-devel-matched-5.14.0-611.30.1.el9_7, kernel-64k-devel-5.14.0-611.30.1.el9_7 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-611.30.1.el9_7, kernel-64k-5.14.0-611.30.1.el9_7, kernel-64k-core-5.14.0-611.30.1.el9_7 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-611.30.1.el9_7, libperf-5.14.0-611.30.1.el9_7
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-611.30.1.el9_7, kernel-rt-64k-5.14.0-611.30.1.el9_7, kernel-rt-64k-core-5.14.0-611.30.1.el9_7 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-611.30.1.el9_7, kernel-rt-core-5.14.0-611.30.1.el9_7, kernel-rt-debug-5.14.0-611.30.1.el9_7 +9
  • RHSA-2026:1690 Released 2026-02-02 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-124.31.1.el10_1, kernel-64k-debug-devel-matched-6.12.0-124.31.1.el10_1, kernel-64k-devel-6.12.0-124.31.1.el10_1 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-124.31.1.el10_1, kernel-64k-6.12.0-124.31.1.el10_1, kernel-64k-core-6.12.0-124.31.1.el10_1 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-124.31.1.el10_1, libperf-6.12.0-124.31.1.el10_1
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-124.31.1.el10_1, kernel-rt-64k-6.12.0-124.31.1.el10_1, kernel-rt-64k-core-6.12.0-124.31.1.el10_1 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-124.31.1.el10_1, kernel-rt-core-6.12.0-124.31.1.el10_1, kernel-rt-debug-6.12.0-124.31.1.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 9AffectedNo fix yet
Red Hat CodeReady Linux Builder EUS (v.9.6)Fixed RHSA-2026:25218
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:1690
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:2212
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:26515
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:23237
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:27731
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:25218
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:1690
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:2264
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:2212
Red Hat Enterprise Linux BaseOS AUS (v.8.4)Fixed RHSA-2026:26535
Red Hat Enterprise Linux BaseOS AUS (v.8.6)Fixed RHSA-2026:25533
Red Hat Enterprise Linux BaseOS E4S (v.8.8)Fixed RHSA-2026:22964
Red Hat Enterprise Linux BaseOS E4S (v.9.2)Fixed RHSA-2026:26515
Red Hat Enterprise Linux BaseOS E4S (v.9.4)Fixed RHSA-2026:23237
Red Hat Enterprise Linux BaseOS EUS (v. 10.0)Fixed RHSA-2026:27731
Red Hat Enterprise Linux BaseOS EUS (v.9.6)Fixed RHSA-2026:25218
Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4)Fixed RHSA-2026:26535
Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6)Fixed RHSA-2026:25533
Red Hat Enterprise Linux BaseOS TUS (v.8.8)Fixed RHSA-2026:22964
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:2264
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:1690
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:2212
Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)Fixed RHSA-2026:27731
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2026:2378
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2026:2378
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:1690
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:2212
Red Hat Enterprise Linux Real Time E4S (v.9.2)Fixed RHSA-2026:26462
Red Hat Enterprise Linux Real Time E4S (v.9.4)Fixed RHSA-2026:23237
Red Hat Enterprise Linux Real Time EUS (v. 10.0)Fixed RHSA-2026:27731
Red Hat Enterprise Linux Real Time EUS (v.9.6)Fixed RHSA-2026:25218
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:1690
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:2212
Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)Fixed RHSA-2026:26462
Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4)Fixed RHSA-2026:23237
Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0)Fixed RHSA-2026:27731
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6)Fixed RHSA-2026:25218
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-40158
  2. 2026-10-03 Alias added: GHSA-4g43-pmw7-v27w
  3. 2026-10-16 Fix available: Linux/[email protected], Linux/Linux@92803b826e40e49a5e8a6e208f4b4574e9d19426 · CNA
  4. 2026-10-16 1 new reference · CNA
  5. 2026-10-21 Fix available: Linux/Linux@423895685f367b5a0a956bd14b02df0192bded4c, Linux/[email protected] · CNA
  6. 2026-10-21 1 new reference · CNA
  7. 2026-10-30 Fix available: Linux/Linux@4549ce1057363c8dc072f40c6aa591c279eafed2, Linux/[email protected] · CNA
  8. 2026-10-30 1 new reference · CNA

References

Other 5

  • 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-2021-02452 Incorrect authorization in Ubuntu linux kernel 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
See all 21741 →

Sources

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