Linux Kernel up to 7.1.8 SMB Client cifs_try_adding_channels use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$5k-$25k0.44-

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.1.182/6.6.151/6.12.103/6.18.44/7.1.8 and classified as very critical. This vulnerability affects the function cifs_try_adding_channels of the component SMB Client. The manipulation leads to use after free. This vulnerability is uniquely identified as CVE-2026-74608. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.182/6.6.151/6.12.103/6.18.44/7.1.8. It has been rated as very critical. This issue affects the function cifs_try_adding_channels of the component SMB Client. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: smb: client: Fix use-after-free in cifs_try_adding_channels() cifs_try_adding_channels() takes a temporary reference to an interface before dropping iface_lock. If cifs_ses_add_channel() fails, it drops that reference and then increments iface->weight_fulfilled. A concurrent interface list refresh can remove the list reference while channel creation is in progress. In that case, the failure-path kref_put() releases the last reference and frees iface. Updating weight_fulfilled afterward then accesses freed memory. Increment weight_fulfilled before dropping the temporary reference, keeping iface alive for the final access.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-74608 since 08/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details are known, but no exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/22/2026).

Upgrading to version 6.1.183, 6.6.152, 6.12.104, 6.18.45 or 7.1.9 eliminates this vulnerability. Applying the patch 64d7584e62ac8cdc750455c5fdc6008fc2de4f06/c292d4686f717c03e5022fc4ae7c782f39a94915/47dfac48bce7198ad4f1a388fc8c9491f878ac3b/1ffacbadc14530e55b8d86f7b917524f6a0fb891/1305eadc6a7d78a8d0a52eee29ddd2d9e8a27805/4986410316b1ae0e63c6ce418e4eb196723626e7 is able to eliminate this problem.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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Version

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
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: Use after free
CWE: CWE-416 / CWE-119
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 6.1.183/6.6.152/6.12.104/6.18.45/7.1.9
Patch: 64d7584e62ac8cdc750455c5fdc6008fc2de4f06/c292d4686f717c03e5022fc4ae7c782f39a94915/47dfac48bce7198ad4f1a388fc8c9491f878ac3b/1ffacbadc14530e55b8d86f7b917524f6a0fb891/1305eadc6a7d78a8d0a52eee29ddd2d9e8a27805/4986410316b1ae0e63c6ce418e4eb196723626e7

Timelineinfo

08/15/2026 CVE reserved
08/22/2026 +7 days Advisory disclosed
08/22/2026 +0 days VulDB entry created
08/22/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-74608 (🔒)
GCVE (CVE): GCVE-0-2026-74608
GCVE (VulDB): GCVE-100-394397

Entryinfo

Created: 08/22/2026 18:13
Changes: 08/22/2026 18:13 (59)
Complete: 🔍
Cache ID: 216::103

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