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TI-2026-84233 Aliases CVE-2026-99270GHSA-7686-ccqp-qmhx

Use-after-free in TCP request socket timer handler in Linux kernel

Priority LOW 35Published · 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: 6 without a fix

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

Summary

The Linux kernel from 4.1.11 before 4.2 and from 4.2 is affected. When TCP socket migration fails in reqsk_timer_handler(), the new request socket is freed while its timer may still be pending, so the timer can later access freed memory. A remote unauthenticated attacker can trigger this under high attack complexity, affecting confidentiality, integrity and availability.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: tcp: Fix potential UAF in reqsk_timer_handler(). When TCP socket migration fails at inet_ehash_insert() in reqsk_timer_handler(), we jump to the no_ownership: label and free the new reqsk immediately with __reqsk_free(). Thus, we must stop the new reqsk's timer before jumping to the label, but the timer might be missed since the cited commit, resulting in UAF. As we are in the original reqsk's timer context, we can safely call timer_delete_sync() for the new reqsk. Let's pass false to __inet_csk_reqsk_queue_drop() to stop the new reqsk's timer.

Why it matters now

EPSS 0.00335 27th percentileScored 2026-11-07
Fix Partial Linux (Linux): 4.2, 6.18.61, 7.1Red 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
LinuxLinux4.1.11 to before 4.24.2Patch availableCNA
LinuxLinux4.2 and later6.18.61, 7.1Patch availableCNA
  • Linux VendorLinux Affected 4.1.11 to before 4.2 Fixed in 4.2 Patch available CNA
  • Linux VendorLinux Affected 4.2 and later Fixed in 6.18.61, 7.1 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

The Linux kernel is fixed in 4.2, 6.18.61 and 7.1. Red Hat has no fix available yet for Red Hat Enterprise Linux 8, 9 and 10 and OpenShift Container Platform 4 and 5, and has no fix planned for Red Hat Enterprise Linux 6.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA Linux (Linux) Fixed in 4.2
  • Fix · CNA Linux (Linux) Fixed in 6.18.61, 7.1

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 5AffectedNo fix yet: Fix deferred
Not affected: 1 product
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-11-03 Threatist record created from CVE-2026-99270
  2. 2026-11-03 Alias added: GHSA-7686-ccqp-qmhx
  3. 2026-11-03 CVSS score added · CNA
  4. 2026-11-03 Priority changed: LOW → MEDIUM
  5. 2026-11-05 Priority changed: MEDIUM → LOW
  6. 2026-11-06 Affected versions changed · Red Hat
  7. 2026-11-06 CVSS score added · Red Hat
  8. 2026-11-06 Fix available: Linux/[email protected], Linux/Linux@b3b56e95f6fad7fa7281450b443e861d82616fdb · CNA
  9. 2026-11-06 1 new reference · CNA

References

Other 2

  • 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