Read the docs
TI-2026-75977 Aliases CVE-2026-98849GHSA-gh42-phxg-w86j

NULL pointer dereference in Linux kernel PFCP socket cleanup

Priority LOW 22Published · Updated

Key facts

Attack vector
—
Privileges required
—
User interaction
—
Attack complexity
—
Impact type
—
Confidentiality · integrity · availability
—
Fix status
Fixed

No CVSS vector from any source. Fix status from CNA.

Summary

The Linux kernel from 6.10 contains a flaw in the PFCP driver where a failed network device registration leaves the UDP socket released twice. When pfcp_newlink() fails after pfcp_dev_init() succeeds, the socket is freed by the core teardown and then freed again by the error path, causing a NULL pointer dereference. A local user who can trigger a device creation failure can crash the system.

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: pfcp: fix socket lifetime on netdevice registration failure pfcp_newlink() creates the UDP socket before register_netdevice(). If registration fails after pfcp_dev_init() succeeds, the core calls pfcp_dev_uninit(), which releases the socket and clears pfcp->sk. The newlink error path then releases it again, causing a NULL pointer dereference. This was observed with failslab fault injection: FAULT_INJECTION: forcing a failure. kobject: kobject_add_internal failed for pfcp0 (error: -12 parent: net) BUG: KASAN: null-ptr-deref in udp_tunnel_sock_release+0x1c/0x50 Read of size 8 at addr 0000000000000120 by task ip/1037 Call trace: show_stack+0x18/0x24 (C) dump_stack_lvl+0x78/0x90 print_report+0x468/0x5cc kasan_report+0xa4/0xf0 __asan_load8+0x7c/0xd0 udp_tunnel_sock_release+0x1c/0x50 pfcp_newlink+0x128/0x184 rtnl_newlink+0x848/0xe44 rtnetlink_rcv_msg+0x468/0x514 netlink_rcv_skb+0xc0/0x1f0 rtnetlink_rcv+0x18/0x24 netlink_unicast+0x4b8/0x558 netlink_sendmsg+0x2b8/0x584 ... Return from pfcp_del_sock() if pfcp->sk is NULL.

Why it matters now

EPSS 0.00168 6th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.12.113, 6.18.56, 7.2.10 +1

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.10 and later6.12.113, 6.18.56, 7.2.10, 7.3Patch availableCNA
  • Linux VendorLinux Affected 6.10 and later Fixed in 6.12.113, 6.18.56, 7.2.10, 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

Linux kernel 6.12.113, 6.18.56, 7.2.10 and 7.3 fix this issue, and the fix is in those versions. Upgrade to one of these fixed versions or later.

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

  • Fix · CNA Linux (Linux) Fixed in 6.12.113, 6.18.56, 7.2.10, 7.3

Vendor assessments

Red Hat

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

Not affected: 7 products
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat OpenShift Container Platform 4
  • Red Hat OpenShift Container Platform 5

Timeline

  1. 2026-10-18 Threatist record created from CVE-2026-98849
  2. 2026-10-18 Alias added: GHSA-gh42-phxg-w86j
  3. 2026-10-19 Fix available: Linux/[email protected] · CNA
  4. 2026-10-24 Affected versions changed · Red Hat
  5. 2026-10-24 CVSS score added · Red Hat
  6. 2026-11-06 Affected versions changed · Red Hat

References

Other 4

  • 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