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TI-2026-81918 Aliases CVE-2026-99211GHSA-rx9x-87v5-hrch

Linux kernel netlink socket filters read data before messages

Priority LOW 22Published · Updated

Key facts

Attack vector
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Privileges required
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User interaction
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Attack complexity
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Impact type
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Confidentiality · integrity · availability
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Fix status
Partial Red Hat: 7 without a fix

No CVSS vector from any source. Fix status from CNA and Red Hat.

Summary

Versions of the Linux kernel from 2.6.26 are affected. The netlink subsystem does not reset the skb network and MAC header offsets before unicast and broadcast delivery, so socket filters can read data from before the message. An unprivileged user who can attach a classic socket filter to a NETLINK_RDMA socket can read this data through the length of a delivered IWPM reply.

Written with Claude Haiku 5.5 from the sources below · 2026-11-07

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: netlink: reset skb headers before unicast and multicast filtering Socket filters can use SKF_NET_OFF and SKF_LL_OFF to read relative to an skb's network and MAC headers. Netlink producers may reserve headroom without resetting those headers, allowing a receiving socket's filter to read data before the initialized message. For example, IWPM HELLO replies are allocated with dev_alloc_skb(), which reserves NET_SKB_PAD bytes. An unprivileged NETLINK_RDMA user can attach a classic socket filter and disclose this headroom through the length of the delivered reply. The resets in netlink_dump() do not help because IWPM sends a separately allocated skb through netlink_unicast(). Reset both headers before running the receiver's filter in unicast and broadcast delivery, as is already done for dump skbs. This also covers other netlink producers that reserve headroom without changing their allocation or message-building code.

Why it matters now

EPSS 0.00167 5th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.273, 5.15.224, 6.6.161 +4Red Hat: 7 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux2.6.26 and later5.10.273, 5.15.224, 6.6.161, 6.12.115, 6.18.59, 7.2.13, 7.3Patch availableCNA
  • Linux VendorLinux Affected 2.6.26 and later Fixed in 5.10.273, 5.15.224, 6.6.161, 6.12.115, 6.18.59, 7.2.13, 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

Update to Linux kernel 5.10.273, 5.15.224, 6.6.161, 6.12.115, 6.18.59, 7.2.13 or 7.3, which contain the fix. Red Hat Enterprise Linux 6 has no fix planned. Red Hat Enterprise Linux 7, 8, 9 and 10 and Red Hat OpenShift Container Platform 4 and 5 have no fix available.

Written with Claude Haiku 5.5 from the sources below · 2026-11-07

  • Fix · CNA Linux (Linux) Fixed in 5.10.273, 5.15.224, 6.6.161, 6.12.115, 6.18.59, 7.2.13, 7.3

Vendor assessments

Red Hat

Red Hat rating: Low. 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 7AffectedNo fix yet: Fix deferred
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

Timeline

  1. 2026-10-28 Threatist record created from CVE-2026-99211
  2. 2026-10-28 Alias added: GHSA-rx9x-87v5-hrch
  3. 2026-10-29 Affected versions changed · Red Hat
  4. 2026-10-29 CVSS score added · Red Hat
  5. 2026-10-30 Fix available: Linux/Linux@4123f8d2099863e2421187af9d87b45e8eebd867, Linux/[email protected], Linux/[email protected] +5 · CNA
  6. 2026-10-30 4 new references · CNA
  7. 2026-11-07 Affected versions changed · Red Hat

References

  • 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