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TI-2026-38198 Aliases CVE-2026-53111GHSA-gj9x-pqvx-p5mh

bpf: test_run: Fix the null pointer dereference issue in bpf_lwt_xmit_push_encap

Priority LOW 24CWE-476Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 3 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: test_run: Fix the null pointer dereference issue in bpf_lwt_xmit_push_encap The bpf_lwt_xmit_push_encap helper needs to access skb_dst(skb)->dev to calculate the needed headroom: err = skb_cow_head(skb, len + LL_RESERVED_SPACE(skb_dst(skb)->dev)); But skb->_skb_refdst may not be initialized when the skb is set up by bpf_prog_test_run_skb function. Executing bpf_lwt_push_ip_encap function in this scenario will trigger null pointer dereference, causing a kernel crash as Yinhao reported: [ 105.186365] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 105.186382] #PF: supervisor read access in kernel mode [ 105.186388] #PF: error_code(0x0000) - not-present page [ 105.186393] PGD 121d3d067 P4D 121d3d067 PUD 106c83067 PMD 0 [ 105.186404] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 105.186412] CPU: 3 PID: 3250 Comm: poc Kdump: loaded Not tainted 6.19.0-rc5 #1 [ 105.186423] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 105.186427] RIP: 0010:bpf_lwt_push_ip_encap+0x1eb/0x520 [ 105.186443] Code: 0f 84 de 01 00 00 0f b7 4a 04 66 85 c9 0f 85 47 01 00 00 31 c0 5b 5d 41 5c 41 5d 41 5e c3 cc cc cc cc 48 8b 73 58 48 83 e6 fe <48> 8b 36 0f b7 be ec 00 00 00 0f b7 b6 e6 00 00 00 01 fe 83 e6 f0 [ 105.186449] RSP: 0018:ffffbb0e0387bc50 EFLAGS: 00010246 [ 105.186455] RAX: 000000000000004e RBX: ffff94c74e036500 RCX: ffff94c74874da00 [ 105.186460] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff94c74e036500 [ 105.186463] RBP: 0000000000000001 R08: 0000000000000002 R09: 0000000000000000 [ 105.186467] R10: ffffbb0e0387bd50 R11: 0000000000000000 R12: ffffbb0e0387bc98 [ 105.186471] R13: 0000000000000014 R14: 0000000000000000 R15: 0000000000000002 [ 105.186484] FS: 00007f166aa4d680(0000) GS:ffff94c8b7780000(0000) knlGS:0000000000000000 [ 105.186490] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 105.186494] CR2: 0000000000000000 CR3: 000000015eade001 CR4: 0000000000770ee0 [ 105.186499] PKRU: 55555554 [ 105.186502] Call Trace: [ 105.186507] <TASK> [ 105.186513] bpf_lwt_xmit_push_encap+0x2b/0x40 [ 105.186522] bpf_prog_a75eaad51e517912+0x41/0x49 [ 105.186536] ? kvm_clock_get_cycles+0x18/0x30 [ 105.186547] ? ktime_get+0x3c/0xa0 [ 105.186554] bpf_test_run+0x195/0x320 [ 105.186563] ? bpf_test_run+0x10f/0x320 [ 105.186579] bpf_prog_test_run_skb+0x2f5/0x4f0 [ 105.186590] __sys_bpf+0x69c/0xa40 [ 105.186603] __x64_sys_bpf+0x1e/0x30 [ 105.186611] do_syscall_64+0x59/0x110 [ 105.186620] entry_SYSCALL_64_after_hwframe+0x76/0xe0 [ 105.186649] RIP: 0033:0x7f166a97455d Temporarily add the setting of skb->_skb_refdst before bpf_test_run to resolve the issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00121 1st percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.1.175, 6.6.141, 6.12.91 +3Red Hat: 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.1 and later6.1.175, 6.6.141, 6.12.91, 6.18.33, 7.0.10, 7.1Patch availableCNA
  • Linux VendorLinux Affected 5.1 and later Fixed in 6.1.175, 6.6.141, 6.12.91, 6.18.33, 7.0.10, 7.1 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.1 to before 6.1.175; 6.2 to before 6.6.141; 6.7 to before 6.12.91; 6.13 to before 6.18.33; 6.19 to before 7.0.10VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.1 to before 6.1.175; 6.2 to before 6.6.141; 6.7 to before 6.12.91; 6.13 to before 6.18.33; 6.19 to before 7.0.10 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.1.175, 6.6.141, 6.12.91, 6.18.33, 7.0.10, 7.1

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 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-53111
  2. 2026-10-03 Alias added: GHSA-gj9x-pqvx-p5mh
  3. 2026-11-06 CISA SSVC decision points changed

References

Patch 6

  • 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-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
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences