Linux Kernel up to 6.18.33/7.0.10 netfs netfs_unlock_abandoned_read_pages no_unlock_folio 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-$25k3.91

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.18.33/7.0.10. It has been rated as very critical. The affected element is the function netfs_unlock_abandoned_read_pages of the component netfs. The manipulation of the argument no_unlock_folio leads to use after free. This vulnerability is traded as CVE-2026-64216. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.18.33/7.0.10. It has been rated as very critical. This issue affects the function netfs_unlock_abandoned_read_pages of the component netfs. The manipulation of the argument no_unlock_folio 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: netfs: Fix potential UAF in netfs_unlock_abandoned_read_pages() netfs_unlock_abandoned_read_pages(rreq) accesses the index of the folios it is wanting to unlock and compares that to rreq->no_unlock_folio so that it doesn't unlock a folio being read for netfs_perform_write() or netfs_write_begin(). However, given that netfs_unlock_abandoned_read_pages() is called _after_ NETFS_RREQ_IN_PROGRESS is cleared, the one folio that it's not allowed to dereference is the one specified by ->no_unlock_folio as ownership immediately reverts to the caller. Fix this by storing the folio pointer instead and using that rather than the index. Also fix netfs_unlock_read_folio() where the same applies.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-64216 since 07/19/2026. 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 07/24/2026).

Upgrading to version 6.18.34 or 7.0.11 eliminates this vulnerability. Applying the patch 6080fa3ecfbb4448a3b47368629534c09b6ec750/3866d015f33aeedf81338dd99154703bef33faef/dbe556972100fabb8e5a1b3d2163831ff07b1e8e is able to eliminate this problem.

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Productinfo

Type

Vendor

Name

Version

License

Website

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
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.18.34/7.0.11
Patch: 6080fa3ecfbb4448a3b47368629534c09b6ec750/3866d015f33aeedf81338dd99154703bef33faef/dbe556972100fabb8e5a1b3d2163831ff07b1e8e

Timelineinfo

07/19/2026 CVE reserved
07/24/2026 +5 days Advisory disclosed
07/24/2026 +0 days VulDB entry created
07/24/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64216 (🔒)
GCVE (CVE): GCVE-0-2026-64216
GCVE (VulDB): GCVE-100-382949

Entryinfo

Created: 07/24/2026 18:10
Changes: 07/24/2026 18:10 (60)
Complete: 🔍
Cache ID: 216::103

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