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TI-2026-60531 Aliases CVE-2026-89488GHSA-vv57-w433-jw5h

openvswitch: Fix CT limit teardown use-after-free

Priority LOW 35Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 16 fixed, 3 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: openvswitch: Fix CT limit teardown use-after-free Packet processing uses CT limit state under RCU, while netns teardown frees that state under ovs_mutex. The CT limit pointer was neither removed from readers nor protected by a grace period, allowing packet processing to dereference the freed state. An unprivileged user can trigger this bug from a user and network namespace, causing a slab-use-after-free in ovs_ct_execute() when the netns is torn down. Publish the CT limit pointer through RCU, remove it before teardown, and wait for readers before freeing its contents. Keep ovs_mutex around individual CT limit updates, and use the RCU read-side lock while GET traverses the RCU-protected limit lists. Netns teardown detaches the RCU-protected CT limit state in the pernet .pre_exit callback while holding ovs_mutex. The pernet core guarantees an RCU grace period between the .pre_exit and .exit callbacks, so the .exit callback completes the teardown without adding any extra synchronization. The netlink command handlers do not need NULL checks because the userspace netlink socket holds an active reference to its network namespace while a request is processed. The per-netns exit path therefore cannot run concurrently with SET, DEL, or GET for that socket's namespace.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00126 2nd percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.270, 5.15.221, 6.1.188 +5Red Hat: 4 advisoriesRed Hat: 16 fixed, 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux4.18 and later5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.51, 7.2.4, 7.3Patch availableCNA
  • Linux VendorLinux Affected 4.18 and later Fixed in 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.51, 7.2.4, 7.3 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 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.51, 7.2.4, 7.3

Red Hat 4 advisories

  • RHSA-2026:95370 Released 2026-11-05 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.66.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.66.1.el9_8, kernel-64k-devel-5.14.0-687.66.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.66.1.el9_8, kernel-64k-5.14.0-687.66.1.el9_8, kernel-64k-core-5.14.0-687.66.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.66.1.el9_8, libperf-5.14.0-687.66.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.66.1.el9_8, kernel-rt-64k-5.14.0-687.66.1.el9_8, kernel-rt-64k-core-5.14.0-687.66.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.66.1.el9_8, kernel-rt-core-5.14.0-687.66.1.el9_8, kernel-rt-debug-5.14.0-687.66.1.el9_8 +9
  • RHSA-2026:95367 Released 2026-11-05 · Red Hat rating Important
    kernel security update
    • 10Base-SMTV kernel-modules-internal-6.12.0-211.74.1.el10_2
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.74.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.74.1.el10_2, kernel-64k-devel-6.12.0-211.74.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.74.1.el10_2, kernel-64k-6.12.0-211.74.1.el10_2, kernel-64k-core-6.12.0-211.74.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.74.1.el10_2, libperf-6.12.0-211.74.1.el10_2
    • Red Hat Enterprise Linux Hidden (v. 10) kernel-modules-internal-6.12.0-211.74.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.74.1.el10_2, kernel-rt-64k-6.12.0-211.74.1.el10_2, kernel-rt-64k-core-6.12.0-211.74.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.74.1.el10_2, kernel-rt-core-6.12.0-211.74.1.el10_2, kernel-rt-debug-6.12.0-211.74.1.el10_2 +9
  • RHSA-2026:95212 Released 2026-11-04 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.184.1.el8_10, kernel-4.18.0-553.184.1.el8_10, kernel-abi-stablelists-4.18.0-553.184.1.el8_10 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.184.1.el8_10
Show 1 more Red Hat advisories
  • RHSA-2026:95100 Released 2026-11-04 · Red Hat rating Important
    kernel-rt security, bug fix, and enhancement update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-553.184.1.rt7.525.el8_10, kernel-rt-core-4.18.0-553.184.1.rt7.525.el8_10, kernel-rt-debug-4.18.0-553.184.1.rt7.525.el8_10 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-553.184.1.rt7.525.el8_10, kernel-rt-core-4.18.0-553.184.1.rt7.525.el8_10, kernel-rt-debug-4.18.0-553.184.1.rt7.525.el8_10 +7

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
10Base-SMTVFixed RHSA-2026:95367
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:95367
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:95370
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:95367
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:95212
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:95370
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:95212
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:95367
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:95370
Red Hat Enterprise Linux Hidden (v. 10)Fixed RHSA-2026:95367
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2026:95100
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2026:95100
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:95367
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:95370
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:95367
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:95370
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-89488
  2. 2026-10-03 Alias added: GHSA-vv57-w433-jw5h
  3. 2026-10-18 CISA SSVC decision points changed
  4. 2026-10-19 Fix available: Linux/[email protected] · CNA
  5. 2026-10-30 Affected versions changed · Red Hat
  6. 2026-11-03 Affected versions changed · Red Hat
  7. 2026-11-04 Fix available: RHSA-2026:95212 · Red Hat
  8. 2026-11-04 Fix available: Red Hat Enterprise Linux BaseOS (v. 8), Red Hat Enterprise Linux CRB (v. 8) · Red Hat
  9. 2026-11-05 Fix available: 10Base-SMTV, Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux AppStream (v. 9) +11 · Red Hat
  10. 2026-11-06 Fix available: RHSA-2026:95370 · Red Hat
  11. 2026-11-06 Fix available: RHSA-2026:95100 · Red Hat
  12. 2026-11-06 Fix available: RHSA-2026:95367 · Red Hat

References

Other 8

  • 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