Linux Kernel up to 6.18.51/7.2.5/7.3-rc2 TCP tcp_sendmsg_locked locking

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.18.51/7.2.5/7.3-rc2 and classified as very critical. This impacts the function tcp_sendmsg_locked of the component TCP. The manipulation results in locking. This vulnerability is identified as CVE-2026-90051. The attack can be executed remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.18.51/7.2.5/7.3-rc2. It has been classified as very critical. Affected is the function tcp_sendmsg_locked of the component TCP. The manipulation with an unknown input leads to a locking vulnerability. CWE is classifying the issue as CWE-667. The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: tcp: reject non zerocopy devmem tx Devmem tcp tx doesn't work without zero-copy, however it's not currently enforced if NETIF_F_SG isn't present. In this case, tcp_sendmsg_locked() will try the copy path and try to copy data from an iovec which consists of offsets into the dma-buf and would normally fail. Moreover, d9c56501c72fd ("net: tcp: block mixing readable and unreadable frags") relies on that and assumes that the devmem binding is present IFF we're using the zero-copy path, which can be used to mix net-iov and pages in a single skb, and break invariants. Let's reject devmem tx without zero-copy. Note, the parameter check the patch is modifying is too loose, we can create an io_uring request with dmabuf_id and all ZC flags, but which won't have the binding. We replace it with stricter validation.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2026-90051 since 09/11/2026. 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 09/17/2026).

Upgrading to version 6.18.52, 7.2.6 or 7.3-rc3 eliminates this vulnerability. Applying the patch 2151b2bcf6fcec52665f606eed20da068447f0b7/b04326c7927af7048fd4e730f5770cca350d0a60/125755776bc6d4dd53eaf551c87e3d460625d638 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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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: Locking
CWE: CWE-667
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 6.18.52/7.2.6/7.3-rc3
Patch: 2151b2bcf6fcec52665f606eed20da068447f0b7/b04326c7927af7048fd4e730f5770cca350d0a60/125755776bc6d4dd53eaf551c87e3d460625d638

Timelineinfo

09/11/2026 CVE reserved
09/17/2026 +6 days Advisory disclosed
09/17/2026 +0 days VulDB entry created
09/17/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-90051 (🔒)
GCVE (CVE): GCVE-0-2026-90051
GCVE (VulDB): GCVE-100-406536

Entryinfo

Created: 09/17/2026 18:29
Changes: 09/17/2026 18:29 (59)
Complete: 🔍
Cache ID: 216::103

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