Linux Kernel up to 6.18.50/7.2.4 ab8500_fg ab8500_fg_remove use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
9.5$5k-$25k0.00

Summaryinfo

A vulnerability identified as very critical has been detected in Linux Kernel up to 6.18.50/7.2.4. This vulnerability affects the function ab8500_fg_remove of the component ab8500_fg. The manipulation leads to use after free. This vulnerability is uniquely identified as CVE-2026-89797. The attack is possible to be carried out remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.18.50/7.2.4 and classified as very critical. This issue affects the function ab8500_fg_remove of the component ab8500_fg. 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: power: supply: ab8500_fg: fix use-after-free on remove ab8500_fg_remove() destroys the driver workqueue while the threaded interrupt handlers are still armed; they are devm-managed and freed only after ->remove() returns, so a handler that fires in that window queues work on the freed workqueue. Tear the workqueue down through devm instead, registering its cleanup after the power supply and before the interrupt requests. devm then frees the interrupts first, so the handlers can no longer queue work, before disabling the delayed and plain work items and destroying the workqueue. Disabling the items, rather than cancelling them, keeps them disabled so no producer (including the power-supply external_power_changed callback) can requeue them. Found by an in-house static analysis tool.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-89797 since 09/11/2026. 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 09/17/2026).

Upgrading to version 6.18.51, 7.2.5 or 7.3-rc1 eliminates this vulnerability. Applying the patch c660c017dec1fd7cd88e1103c5ae1aae6ce636bf/013731074ab6a8d11ec209eee64c5b2656954479/75b1e88d34254f4fb7753345e21bfee47abddd7f is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-3438). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

  • Open Source Linux Kernel

Productinfo

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Vendor

Name

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

EPSS Score: 🔒
EPSS Percentile: 🔒

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 6.18.51/7.2.5/7.3-rc1
Patch: c660c017dec1fd7cd88e1103c5ae1aae6ce636bf/013731074ab6a8d11ec209eee64c5b2656954479/75b1e88d34254f4fb7753345e21bfee47abddd7f

Timelineinfo

09/11/2026 CVE reserved
09/16/2026 +5 days Advisory disclosed
09/16/2026 +0 days VulDB entry created
09/17/2026 +1 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-89797 (🔒)
GCVE (CVE): GCVE-0-2026-89797
GCVE (VulDB): GCVE-100-405617
CERT Bund: WID-SEC-2026-3438 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 09/16/2026 12:52
Updated: 09/17/2026 17:38
Changes: 09/16/2026 12:52 (59), 09/17/2026 17:38 (7)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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