Linux Kernel up to 6.12.112/6.18.55/7.2.8/7.3-rc4 SMB Client cifs_atomic_open missing release of file descriptor or handle after effective lifetime

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k1.00+

Summaryinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.12.112/6.18.55/7.2.8/7.3-rc4. Impacted is the function cifs_atomic_open of the component SMB Client. Such manipulation leads to missing release of file descriptor or handle after effective lifetime. This vulnerability is listed as CVE-2026-98451. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.12.112/6.18.55/7.2.8/7.3-rc4. Affected by this issue is the function cifs_atomic_open of the component SMB Client. The manipulation with an unknown input leads to a missing release of file descriptor or handle after effective lifetime vulnerability. Using CWE to declare the problem leads to CWE-775. The product does not release a file descriptor or handle after its effective lifetime has ended, i.e., after the file descriptor/handle is no longer needed. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: smb: client: use finish_no_open() for non-regular inodes An O_CREAT open can find an existing symlink or another non-regular inode. cifs_atomic_open() calls finish_open() on it and attaches a cifsFileInfo. Symlink inodes have no CIFS release operation, so the dentry reference held by cifsFileInfo is leaked. FMODE_OPENED also prevents the VFS from following the symlink. Track whether cifs_do_create() returned an open server handle. For non-regular inodes, close the handle if present, remove the pending open, and call finish_no_open() so the VFS can continue the lookup. Do not set FMODE_CREATED unless a regular file was opened. For O_NOFOLLOW with __O_REGULAR, return -ELOOP before the VFS's -EFTYPE check. Defer closing a legacy POSIX handle on a non-regular inode until after inode lookup. This avoids closing it again if lookup fails.

The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2026-98451 since 09/25/2026. The exploitation is known to be easy. The attack may be launched remotely. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 10/18/2026).

Upgrading to version 6.12.113, 6.18.56, 7.2.9 or 7.3-rc5 eliminates this vulnerability. Applying the patch ed03d547598c92a036f20e89156540995cac889a/70a7918fda54a06d836acc91eb9a3c7e860fe0a0/3c07deb26273155c180aedfd9041ab58015d2521/e66cf1625ec4a3fe68346119f371def713fd0a4d is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
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: Missing release of file descriptor or handle after effective lifetime
CWE: CWE-775 / CWE-400 / 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 6.12.113/6.18.56/7.2.9/7.3-rc5
Patch: ed03d547598c92a036f20e89156540995cac889a/70a7918fda54a06d836acc91eb9a3c7e860fe0a0/3c07deb26273155c180aedfd9041ab58015d2521/e66cf1625ec4a3fe68346119f371def713fd0a4d

Timelineinfo

09/25/2026 CVE reserved
10/18/2026 +23 days Advisory disclosed
10/18/2026 +0 days VulDB entry created
10/18/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-98451 (🔒)
GCVE (CVE): GCVE-0-2026-98451
GCVE (VulDB): GCVE-100-421778

Entryinfo

Created: 10/18/2026 17:38
Changes: 10/18/2026 17:38 (59)
Complete: 🔍
Cache ID: 216::103

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