Linux Kernel up to 7.3-rc3 SMB Client cifs_get_tcp_session memory leak

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.55

Summaryinfo

A vulnerability was found in Linux Kernel up to 7.3-rc3. It has been rated as critical. This issue affects the function cifs_get_tcp_session of the component SMB Client. Performing a manipulation results in memory leak. This vulnerability is cataloged as CVE-2026-98172. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 7.3-rc3. This affects the function cifs_get_tcp_session of the component SMB Client. The manipulation with an unknown input leads to a memory leak vulnerability. CWE is classifying the issue as CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix smbd_connection leak on cifs_get_tcp_session() error When an RDMA connection is successfully established via smbd_get_connection() but cifs_get_tcp_session() later fails (e.g. kthread_create() returns an error), the error path frees tcp_ses without first destroying the smbd_connection. Fix this by calling smbd_destroy() in the out_err cleanup path before kfree(tcp_ses). smbd_destroy() safely handles the case where smbd_conn is NULL, so it can be called unconditionally.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-98172 since 09/25/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/06/2026). The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

Upgrading to version 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8 or 7.3-rc4 eliminates this vulnerability. Applying the patch 3164402c58940ff58a3cecdb026405f07b0253af/e3344bb0ff5ec8a276f42239e140f5442841ef23/5c908e49d349266dff0c86dda6a05df0ff19b824/928edc4bd6a617caabeb575fc13c254d9df623c4/b26a3fcf2f1c2cadba400290b639f01395db8fc8/e75c96157d45e498970158c8f7373d90102e33b9 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
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: Memory leak
CWE: CWE-401 / 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 6.1.189/6.6.158/6.12.112/6.18.54/7.2.8/7.3-rc4
Patch: 3164402c58940ff58a3cecdb026405f07b0253af/e3344bb0ff5ec8a276f42239e140f5442841ef23/5c908e49d349266dff0c86dda6a05df0ff19b824/928edc4bd6a617caabeb575fc13c254d9df623c4/b26a3fcf2f1c2cadba400290b639f01395db8fc8/e75c96157d45e498970158c8f7373d90102e33b9

Timelineinfo

09/25/2026 CVE reserved
10/06/2026 +11 days Advisory disclosed
10/06/2026 +0 days VulDB entry created
10/06/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-98172 (🔒)
GCVE (CVE): GCVE-0-2026-98172
GCVE (VulDB): GCVE-100-414099

Entryinfo

Created: 10/06/2026 12:45
Changes: 10/06/2026 12:45 (59)
Complete: 🔍
Cache ID: 216::103

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