Linux Kernel up to 6.18.51/7.2.5 dm-pcache cache_writeback_fn infinite loop

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4.0	$0-$5k	0.39-

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.18.51/7.2.5. It has been classified as problematic. This issue affects the function cache_writeback_fn of the component dm-pcache. The manipulation leads to infinite loop. This vulnerability is traded as CVE-2026-93198. An attack has to be approached locally. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Linux Kernel up to 6.18.51/7.2.5. This issue affects the function cache_writeback_fn of the component dm-pcache. The manipulation with an unknown input leads to a infinite loop vulnerability. Using CWE to declare the problem leads to CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: dm-pcache: validate the persisted dirty_tail chain at load The writeback worker follows the persisted dirty_tail chain, which is decoded from the cache device independently of the key_tail chain that cache_replay() walks and bounds. A crafted image, whose on-media fields are authenticated only by a crc32c with a fixed seed, can aim dirty_tail at a chain of last ksets that never terminates, so cache_writeback_fn() re-arms itself with no delay forever. Walk the dirty_tail chain once at load with the same hop cap cache_replay() uses and fail the table load with -EIO if it does not reach an end within n_segs hops.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2026-93198 since 09/17/2026. The exploitation is known to be easy. Attacking locally is a requirement. Additional levels of successful authentication are needed for exploitation. 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.

Upgrading to version 6.18.52, 7.2.6 or 7.3-rc1 eliminates this vulnerability. Applying the patch 8195cf3f4a82ef49d9b0651c507ed0784caf23fb/4822a030929e0e77aa380722dc42e3e4c9edd346/58d620ee9e01d4bdbceaf2ae1450d307a2a9d58b is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
• 6.18.12
• 6.18.13
• 6.18.14
• 6.18.15
• 6.18.16
• 6.18.17
• 6.18.18
• 6.18.19
• 6.18.20
• 6.18.21
• 6.18.22
• 6.18.23
• 6.18.24
• 6.18.25
• 6.18.26
• 6.18.27
• 6.18.28
• 6.18.29
• 6.18.30
• 6.18.31
• 6.18.32
• 6.18.33
• 6.18.34
• 6.18.35
• 6.18.36
• 6.18.37
• 6.18.38
• 6.18.39
• 6.18.40
• 6.18.41
• 6.18.42
• 6.18.43
• 6.18.44
• 6.18.45
• 6.18.46
• 6.18.47
• 6.18.48
• 6.18.49
• 6.18.50
• 6.18.51
• 7.2.0
• 7.2.1
• 7.2.2
• 7.2.3
• 7.2.4
• 7.2.5

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
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CPE 2.2info

• 🔒
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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.2
VulDB Meta Temp Score: 4.0

VulDB Base Score: 4.2
VulDB Temp Score: 4.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Infinite loop
CWE: CWE-835 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Today	Unlock	Unlock	Unlock	Unlock

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-rc1
Patch: 8195cf3f4a82ef49d9b0651c507ed0784caf23fb/4822a030929e0e77aa380722dc42e3e4c9edd346/58d620ee9e01d4bdbceaf2ae1450d307a2a9d58b

Timelineinfo

09/17/2026 CVE reserved
09/17/2026 +0 days VulDB entry created
09/18/2026 +0 days Advisory disclosed
09/18/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-93198 (🔒)
GCVE (CVE): GCVE-0-2026-93198
GCVE (VulDB): GCVE-100-407279

Entryinfo

Created: 09/18/2026 00:15
Changes: 09/18/2026 00:15 (59)
Complete: 🔍
Cache ID: 216::103

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