Linux Kernel up to 7.1.4 XDP Master Redirect net/core/filter.c xdp_master_redirect null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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7.2$0-$5k2.10

Summaryinfo

A vulnerability was found in Linux Kernel up to 7.1.4 and classified as critical. Affected by this issue is the function xdp_master_redirect of the file net/core/filter.c of the component XDP Master Redirect. The manipulation results in null pointer dereference. This vulnerability is cataloged as CVE-2026-64545. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.1.4. It has been classified as critical. Affected is the function xdp_master_redirect of the file net/core/filter.c of the component XDP Master Redirect. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net, bpf: check master for NULL in xdp_master_redirect() xdp_master_redirect() dereferences the result of netdev_master_upper_dev_get_rcu() without a NULL check, but that helper returns NULL when the receiving device has no upper-master adjacency. The reach guard only checks netif_is_bond_slave(). On bond slave release bond_upper_dev_unlink() drops the upper-master adjacency before clearing IFF_SLAVE, so an XDP_TX reaching xdp_master_redirect() in that window still passes netif_is_bond_slave() while master is already NULL, and faults on master->flags at offset 0xb0: BUG: kernel NULL pointer dereference, address: 00000000000000b0 RIP: 0010:xdp_master_redirect (net/core/filter.c:4432) Call Trace: xdp_master_redirect (net/core/filter.c:4432) bpf_prog_run_generic_xdp (include/net/xdp.h:700) do_xdp_generic (net/core/dev.c:5608) __netif_receive_skb_one_core (net/core/dev.c:6204) process_backlog (net/core/dev.c:6319) __napi_poll (net/core/dev.c:7729) net_rx_action (net/core/dev.c:7792) handle_softirqs (kernel/softirq.c:622) __dev_queue_xmit (include/linux/bottom_half.h:33) packet_sendmsg (net/packet/af_packet.c:3082) __sys_sendto (net/socket.c:2252) Kernel panic - not syncing: Fatal exception in interrupt The missing check dates back to the original code; commit 1921f91298d1 ("net, bpf: fix null-ptr-deref in xdp_master_redirect() for down master") later added the master->flags read where the fault now lands but kept the unconditional deref. Check master for NULL before use; a NULL master is treated the same as one that is not up.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2026-64545 since 07/19/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 07/27/2026).

Upgrading to version 5.15.212, 6.1.178, 6.6.145, 6.12.97, 6.18.40, 7.1.5 or 7.2-rc1 eliminates this vulnerability. Applying the patch c99ca049e910d61ddbd28cc2c47242f2bfbb4970/e2a56441233131fe18a76001de347ecda217e40c/3876318ea54e83eb70982b8280a3c5e4e32269bf/4edbcacca09f92b85d3951b6add11894b20a84bc/03b743586a2469744e96e9c1015096d07240935d/89c103d702b25ceb2d097faf854deb47b53b17ff/e82d8cc4321c373dc46e741cd2dfdaa7921fddb7 is able to eliminate this problem.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.2

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.15.212/6.1.178/6.6.145/6.12.97/6.18.40/7.1.5/7.2-rc1
Patch: c99ca049e910d61ddbd28cc2c47242f2bfbb4970/e2a56441233131fe18a76001de347ecda217e40c/3876318ea54e83eb70982b8280a3c5e4e32269bf/4edbcacca09f92b85d3951b6add11894b20a84bc/03b743586a2469744e96e9c1015096d07240935d/89c103d702b25ceb2d097faf854deb47b53b17ff/e82d8cc4321c373dc46e741cd2dfdaa7921fddb7

Timelineinfo

07/19/2026 CVE reserved
07/27/2026 +8 days Advisory disclosed
07/27/2026 +0 days VulDB entry created
07/27/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64545 (🔒)
GCVE (CVE): GCVE-0-2026-64545
GCVE (VulDB): GCVE-100-383604

Entryinfo

Created: 07/27/2026 23:23
Changes: 07/27/2026 23:23 (60)
Complete: 🔍
Cache ID: 216::103

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