Linux Kernel up to 7.2-rc2 ebtables vfree chainstack uninitialized pointer

CVSS Meta Temp Score
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CTI Interest Score
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9.5$0-$5k1.55-

Summaryinfo

A vulnerability classified as very critical has been found in Linux Kernel up to 7.2-rc2. This vulnerability affects the function vfree of the component ebtables. This manipulation of the argument chainstack causes uninitialized pointer. This vulnerability is handled as CVE-2026-64413. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as very critical was found in Linux Kernel up to 7.2-rc2. Affected by this vulnerability is the function vfree of the component ebtables. The manipulation of the argument chainstack with an unknown input leads to a uninitialized pointer vulnerability. The CWE definition for the vulnerability is CWE-824. The product accesses or uses a pointer that has not been initialized. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: netfilter: ebtables: zero chainstack array sashiko reports: looking at ebtables table translation, could a sparse cpu_possible_mask lead to an uninitialized pointer free? If cpu_possible_mask is sparse (for example, CPU 0 and CPU 2 are possible, but CPU 1 is not), the allocation loop skips CPU 1. If vmalloc_node() fails at CPU 2, the cleanup loop will blindly decrement and call vfree() on newinfo->chainstack[1]. Not a real-world bug, such allocation isn't expected to fail in the first place.

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2026-64413 since 07/19/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/25/2026).

Upgrading to version 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.97, 6.18.39, 7.1.4 or 7.2-rc3 eliminates this vulnerability. Applying the patch 2ade612967e2cdfb9290ebcb773f302c82f311fa/42bef500d07b5769d916e9122a3e3fa3fd2245ef/fc7f105451044501a50cfd530cfa3b472c54acbc/9e6c5169db423e51dcc66a73fd15409c0d38e088/29bf41a9b59aff9f6197df58641a00037d567ca8/9f74d28e903fa4fdf82f870d0aeadddc8196e41c/5ee856e4208acafaaaf7b84824d39b78c21345d6/cbfe53599eebffd188938ab6774cc41794f6f9d5 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: 10.0
VulDB Meta Temp Score: 9.5

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
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: Uninitialized pointer
CWE: CWE-824 / CWE-908
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

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 5.10.261/5.15.212/6.1.178/6.6.145/6.12.97/6.18.39/7.1.4/7.2-rc3
Patch: 2ade612967e2cdfb9290ebcb773f302c82f311fa/42bef500d07b5769d916e9122a3e3fa3fd2245ef/fc7f105451044501a50cfd530cfa3b472c54acbc/9e6c5169db423e51dcc66a73fd15409c0d38e088/29bf41a9b59aff9f6197df58641a00037d567ca8/9f74d28e903fa4fdf82f870d0aeadddc8196e41c/5ee856e4208acafaaaf7b84824d39b78c21345d6/cbfe53599eebffd188938ab6774cc41794f6f9d5

Timelineinfo

07/19/2026 CVE reserved
07/25/2026 +6 days Advisory disclosed
07/25/2026 +0 days VulDB entry created
07/25/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64413 (🔒)
GCVE (CVE): GCVE-0-2026-64413
GCVE (VulDB): GCVE-100-383221

Entryinfo

Created: 07/25/2026 18:36
Changes: 07/25/2026 18:36 (60)
Complete: 🔍
Cache ID: 216::103

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