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TI-2026-75618 Aliases CVE-2026-98490GHSA-4r7h-j2g8-7vfx

Use-after-free in Linux kernel openvswitch conntrack helpers

Priority MEDIUM 43Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 6 without a fix

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

Summary

The Linux kernel openvswitch conntrack code is affected in versions from 4.3 until the fixed releases listed in the solution. When a connection is not yet confirmed, a conntrack helper stores a raw pointer to the extension area in the expectations list, and later extension allocations can move that area and leave the pointer invalid, so it is used after it is freed when the expectation is removed (CWE not listed). An unauthenticated remote attacker can trigger this without user interaction, with high impact to confidentiality, integrity and availability.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: net: openvswitch: conntrack: fix helper UAF due to extensions realloc While calling the helpers, a raw pointer to the extensions area is wired into expectations list: -> nf_ct_helper() -> helper->help() -> nf_ct_expect_related_report() -> nf_ct_expect_insert() -> hlist_add_head_rcu(&exp->lnode, &master_help->expectations) In case the connection is not confirmed yet, more extensions can be added afterwards with *_ext_add() calls reallocating the extension space and leaving the now invalid pointer in the expectations list that is later accessed while removing the expectation. Make sure that helpers are called at the end after all the other extensions are already added. Note that the helper rejection now leaves the mark and labels set, but that's not different from how the NAT was handled before or how the mark and the labels were handled on confirmation failure. And there are no atomicity guarantees provided by the API anyway.

Why it matters now

EPSS 0.00695 53rd percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.273, 5.15.224, 6.1.191 +5Red Hat: 6 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux4.3 and later5.10.273, 5.15.224, 6.1.191, 6.6.160, 6.12.112, 6.18.55, 7.2.9, 7.3Patch availableCNA
  • Linux VendorLinux Affected 4.3 and later Fixed in 5.10.273, 5.15.224, 6.1.191, 6.6.160, 6.12.112, 6.18.55, 7.2.9, 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

Install a Linux kernel release that contains the fix for your branch: 5.10.273, 5.15.224, 6.1.191, 6.6.160, 6.12.112, 6.18.55, 7.2.9 or 7.3. Red Hat lists Red Hat Enterprise Linux 7, 8, 9 and 10 and Red Hat OpenShift Container Platform 4 and 5 as affected, with no available fix plan.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

  • Fix · CNA Linux (Linux) Fixed in 5.10.273, 5.15.224, 6.1.191, 6.6.160, 6.12.112, 6.18.55, 7.2.9, 7.3

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 7AffectedNo fix yet
Red Hat Enterprise Linux 8AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Not affected: 1 product
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-10-18 Threatist record created from CVE-2026-98490
  2. 2026-10-18 Alias added: GHSA-4r7h-j2g8-7vfx
  3. 2026-10-19 Fix available: Linux/[email protected] · CNA
  4. 2026-10-20 Affected versions changed · Red Hat
  5. 2026-10-20 CVSS score added · Red Hat
  6. 2026-10-21 Fix available: Linux/Linux@18866dc1f525f9ee4de7709529d1ae1af8d8e8be, Linux/[email protected] · CNA
  7. 2026-10-21 1 new reference · CNA
  8. 2026-10-24 CVSS score added · CNA
  9. 2026-10-24 Priority changed: LOW → MEDIUM
  10. 2026-10-30 Affected versions changed · Red Hat
  11. 2026-10-30 Fix available: Linux/[email protected], Linux/[email protected], Linux/[email protected] +3 · CNA
  12. 2026-10-30 3 new references · CNA
  13. 2026-10-31 EPSS moved to the 50th–90th percentile

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