Linux Kernel up to 7.2.5 test_hmm lib/test_hmm.c dmirror_fault infinite loop

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.5$0-$5k0.39-

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 7.2.5. Impacted is the function dmirror_fault of the file lib/test_hmm.c of the component test_hmm. The manipulation results in infinite loop. This vulnerability is known as CVE-2026-90391. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.2.5. It has been classified as critical. Affected is the function dmirror_fault of the file lib/test_hmm.c of the component test_hmm. The manipulation with an unknown input leads to a infinite loop vulnerability. CWE is classifying the issue as CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: lib/test_hmm: fail dmirror_fault() when the mirrored mm is gone dmirror_fault() is called from the dmirror_read() and dmirror_write() retry loops after dmirror_do_read() or dmirror_do_write() finds a missing device page table entry. If the mirrored mm has already exited, mmget_not_zero() fails. The current code returns 0 in that case, which tells the caller that faulting succeeded even though no page was faulted and no device page table entry was installed. The caller then retries the same address, hits -ENOENT again, and can loop forever without making progress. Return -EFAULT instead, so the ioctl fails when the mirrored mm is no longer faultable.

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2026-90391 since 09/11/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Successful exploitation requires user interaction by the victim. 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 09/17/2026). This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

Upgrading to version 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.52, 7.2.6 or 7.3-rc1 eliminates this vulnerability. Applying the patch 50606ced303782f8715e2d0b98ca374ea498fa29/541a67f21ab807c8dbc0ea88d5a2eb73b2618090/d8e64ffab01e032ae29159d27230ace8cf8bdc80/2636569ea7c19d9a40db4a1e8d0a027bdacf1569/701347e31aa607f3782403151a3125729d685275/af7a6d6ec36a16a583ba2e4e9984c3cf1fe34655/a2074f86fc9653831e4fb7b711bb715db330f182/6a8024511ddf4877435c34fb3d6028aa8e590649 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.7
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
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: Infinite loop
CWE: CWE-835 / 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 5.10.270/5.15.221/6.1.188/6.6.157/6.12.110/6.18.52/7.2.6/7.3-rc1
Patch: 50606ced303782f8715e2d0b98ca374ea498fa29/541a67f21ab807c8dbc0ea88d5a2eb73b2618090/d8e64ffab01e032ae29159d27230ace8cf8bdc80/2636569ea7c19d9a40db4a1e8d0a027bdacf1569/701347e31aa607f3782403151a3125729d685275/af7a6d6ec36a16a583ba2e4e9984c3cf1fe34655/a2074f86fc9653831e4fb7b711bb715db330f182/6a8024511ddf4877435c34fb3d6028aa8e590649

Timelineinfo

09/11/2026 CVE reserved
09/17/2026 +6 days Advisory disclosed
09/17/2026 +0 days VulDB entry created
09/17/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-90391 (🔒)
GCVE (CVE): GCVE-0-2026-90391
GCVE (VulDB): GCVE-100-406950

Entryinfo

Created: 09/17/2026 22:12
Changes: 09/17/2026 22:12 (60)
Complete: 🔍
Cache ID: 216::103

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