Evidence-led vulnerability intelligence · 2026-07-01 19:46 IST

CVE-2026-53353

In the Linux kernel, the following vulnerability has been resolved: hsr: Remove WARN_ONCE() in hsr_addr_is_self(). syzbot reported the warning [0] in hsr_addr_is_self(), whose assumption is simply wrong. hsr->self_node is cleared in hsr_del_self_node(), which is called from hsr_dellink(). Since dev->rtnl_link_ops->dellink() is called before unregister_netdevice_many(), there is a window when user can find the device but without hsr->self_node. Let's remove WARN_ONCE() in hsr_addr_is_self(). [0]: HSR: No self node WARNING: net/hsr/hsr_framereg.c:39 at hsr_addr_is_self+0x211/0x3f0 net/hsr/hsr_framereg.c:39, CPU#0: syz.4.16848/17220 Modules linked in: CPU: 0 UID: 0 PID: 17220 Comm: syz.4.16848 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:hsr_addr_is_self+0x211/0x3f0 net/hsr/hsr_framereg.c:39 Code: 33 2f 41 0f b7 dd 89 ee 09 de 31 ff e8 c8 b4 c6 f6 09 dd 74 54 e8 0f b0 c6 f6 31 ed eb 53 e8 06 b0 c6 f6 48 8d 3d 2f 50 9c 04 <67> 48 0f b9 3a 31 ed eb 42 e8 c1 13 1f 00 89 c5 31 ff 89 c6 e8 96 RSP: 0018:ffffc900041c70e0 EFLAGS: 00010283 RAX: ffffffff8afdc6ca RBX: ffffffff8afdc4e6 RCX: 0000000000080000 RDX: ffffc90010493000 RSI: 0000000000000948 RDI: ffffffff8f9a1700 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc900041c71e8 R11: fffff52000838e3f R12: dffffc0000000000 R13: ffff888041f9e3c0 R14: ffff888086ee3802 R15: 0000000000000000 FS: 00007f6fe985d6c0(0000) GS:ffff888126176000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f80bd437dac CR3: 0000000025096000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: <TASK> check_local_dest net/hsr/hsr_forward.c:592 [inline] fill_frame_info net/hsr/hsr_forward.c:728 [inline] hsr_forward_skb+0xa11/0x2a80 net/hsr/hsr_forward.c:739 hsr_dev_xmit+0x253/0x370 net/hsr/hsr_device.c:236 __netdev_start_xmit include/linux/netdevice.h:5368 [inline] netdev_start_xmit include/linux/netdevice.h:5377 [inline] xmit_one net/core/dev.c:3888 [inline] dev_hard_start_xmit+0x2df/0x860 net/core/dev.c:3904 __dev_queue_xmit+0x1428/0x3900 net/core/dev.c:4870 neigh_output include/net/neighbour.h:556 [inline] ip_finish_output2+0xcec/0x10b0 net/ipv4/ip_output.c:237 ip_send_skb net/ipv4/ip_output.c:1510 [inline] ip_push_pending_frames+0x8b/0x110 net/ipv4/ip_output.c:1530 raw_sendmsg+0x1547/0x1a50 net/ipv4/raw.c:659 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg net/socket.c:802 [inline] ____sys_sendmsg+0x7da/0x9c0 net/socket.c:2698 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2752 __sys_sendmsg net/socket.c:2784 [inline] __do_sys_sendmsg net/socket.c:2789 [inline] __se_sys_sendmsg net/socket.c:2787 [inline] __x64_sys_sendmsg+0x1c3/0x2a0 net/socket.c:2787 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6feb62ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6fe985d028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f6feb8a6090 RCX: 00007f6feb62ce59 RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000004 RBP: 00007f6feb6c2d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6feb8a6128 R14: 00007f6feb8a6090 R15: 00007ffcf01cc488 </TASK>

MEDIUM · 5.5LinuxmacOS / Apple

Executive briefing

The source record describes: In the Linux kernel, the following vulnerability has been resolved: hsr: Remove WARN_ONCE() in hsr_addr_is_self(). syzbot reported the warning [0] in hsr_addr_is_self(), whose assumption is simply wrong. hsr->self_node is cleared in hsr_del_self_node(), which is called from hsr_dellink(). Since dev->rtnl_link_ops->dellink() is called before unregister_netdevice_many(), there is a window when user can find the device but without hsr->self_node. Let's remove WARN_ONCE() in hsr_addr_is_self(). [0]: HSR: No self node WARNING: net/hsr/hsr_framereg.c:39 at hsr_addr_is_self+0x211/0x3f0 net/hsr/hsr_framereg.c:39, CPU#0: syz.4.16848/17220 Modules linked in: CPU: 0 UID: 0 PID: 17220 Comm: syz.4.16848 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:hsr_addr_is_self+0x211/0x3f0 net/hsr/hsr_framereg.c:39 Code: 33 2f 41 0f b7 dd 89 ee 09 de 31 ff e8 c8 b4 c6 f6 09 dd 74 54 e8 0f b0 c6 f6 31 ed eb 53 e8 06 b0 c6 f6 48 8d 3d 2f 50 9c 04 <67> 48 0f b9 3a 31 ed eb 42 e8 c1 13 1f 00 89 c5 31 ff 89 c6 e8 96 RSP: 0018:ffffc900041c70e0 EFLAGS: 00010283 RAX: ffffffff8afdc6ca RBX: ffffffff8afdc4e6 RCX: 0000000000080000 RDX: ffffc90010493000 RSI: 0000000000000948 RDI: ffffffff8f9a1700 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc900041c71e8 R11: fffff52000838e3f R12: dffffc0000000000 R13: ffff888041f9e3c0 R14: ffff888086ee3802 R15: 0000000000000000 FS: 00007f6fe985d6c0(0000) GS:ffff888126176000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f80bd437dac CR3: 0000000025096000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: <TASK> check_local_dest net/hsr/hsr_forward.c:592 [inline] fill_frame_info net/hsr/hsr_forward.c:728 [inline] hsr_forward_skb+0xa11/0x2a80 net/hsr/hsr_forward.c:739 hsr_dev_xmit+0x253/0x370 net/hsr/hsr_device.c:236 __netdev_start_xmit include/linux/netdevice.h:5368 [inline] netdev_start_xmit include/linux/netdevice.h:5377 [inline] xmit_one net/core/dev.c:3888 [inline] dev_hard_start_xmit+0x2df/0x860 net/core/dev.c:3904 __dev_queue_xmit+0x1428/0x3900 net/core/dev.c:4870 neigh_output include/net/neighbour.h:556 [inline] ip_finish_output2+0xcec/0x10b0 net/ipv4/ip_output.c:237 ip_send_skb net/ipv4/ip_output.c:1510 [inline] ip_push_pending_frames+0x8b/0x110 net/ipv4/ip_output.c:1530 raw_sendmsg+0x1547/0x1a50 net/ipv4/raw.c:659 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg net/socket.c:802 [inline] ____sys_sendmsg+0x7da/0x9c0 net/socket.c:2698 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2752 __sys_sendmsg net/socket.c:2784 [inline] __do_sys_sendmsg net/socket.c:2789 [inline] __se_sys_sendmsg net/socket.c:2787 [inline] __x64_sys_sendmsg+0x1c3/0x2a0 net/socket.c:2787 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6feb62ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6fe985d028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f6feb8a6090 RCX: 00007f6feb62ce59 RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000004 RBP: 00007f6feb6c2d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6feb8a6128 R14: 00007f6feb8a6090 R15: 00007ffcf01cc488 </TASK> The practical risk depends on whether an affected product/version is present, reachable and configured in an exploitable way. Review the affected-product evidence and linked vendor advisories before assigning exposure status.

Assessment: Potential exposure only — validate the installed product, exact version, configuration and vendor applicability before treating an asset as confirmed vulnerable.

Evidence confidence: Moderate Evidence-derived, not an exploitability verdict

Severity & attack characteristics

5.5 / 10 · 3.1

CVSS vector:
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack vectorL
Attack complexityL
Privileges requiredL
User interactionN
ScopeU
Confidentiality impactN
Integrity impactN
Availability impactH

Technical explanation & impact

The technical mechanism is not expanded beyond the source description unless a referenced advisory supplies additional evidence. Read the linked vendor/CERT advisories for root-cause detail.

Potential impact must be interpreted from the published CVSS impact metrics and the affected component. A CVSS impact score is not proof that a particular asset is exploitable.

Weakness classification

NVD-CWE-noinfo

Affected products and versions

Products below are parsed from NVD vulnerable CPE configuration entries. Version boundaries are shown as published; verify applicability with the vendor.

VendorProductVersion evidence
linuxlinux_kernelfrom (inclusive) 6.19; before 7.0.13 · CPE version 7.1 · CPE version 7.1 · CPE version 7.1 · CPE version 7.1 · CPE version 7.1 · CPE version 7.1

Remediation & validation

  1. Identify exposure by comparing the affected product and version ranges with your asset inventory, SBOM and externally exposed services.
  2. Review the linked vendor security advisory or patch notes. Upgrade to a vendor-confirmed fixed release; do not infer a fixed version from the CVE description.
  3. Until patched, consider restricting network access or disabling the affected feature where operationally safe. These are temporary controls, not a substitute for a vendor fix.
  4. Validate the remediation with a version check and vulnerability rescan, then retain change evidence.

No fixed version is displayed unless it is explicitly established by a vendor advisory. Follow the vendor's release notes for exact product and branch applicability.

Vendor advisories, patches & exploit references

Open NVD record ← Back to CVE Watch

Threat intelligence, made actionable · CVE data sourced from the NVD