Linux Kernel: security vulnerability (CVE-2026-89900)

What is affected, what to do

In the Linux kernel, the following vulnerability has been resolved: media: cec: core: Fix kmemleak due to missed rc_free_device() call The commit dccc0c3ddf8f ("media: rc: fix race between unregister and urb/irq callbacks") removed the implicit call to rc_free_device() from rc_unregister_device(). However, the commit missed to remove the NULL assignment of adap->rc that is now causing rc_free_device() to never be called on an allocated rc device. kmemleak reports following after e.g. dw-hdmi unbind: unreferenced object 0xffff00010ac10000 (size 4096): comm "kworker/u16:1", pid 39, jiffies 4294897739 hex dump (first 32 bytes): 20 23 4b 0a 01 00 ff ff 08 00 c1 0a 01 00 ff ff #K............. 08 00 c1 0a 01 00 ff ff 00 00 00 00 00 00 00 00 ................ backtrace (crc e11baccc): kmemleak_alloc+0x38/0x44 __kmalloc_cache_noprof+0x4a8/0x5e0 rc_allocate_device+0x48/0x2a0 cec_allocate_adapter+0x3ac/0x800 dw_hdmi_cec_probe+0x264/0x634 platform_probe+0xc0/0x188 really_probe+0x4a4/0x8e0 __driver_probe_device+0x2f8/0x440 driver_probe_device+0x60/0x160 __device_attach_driver+0x1a0/0x2a0 bus_for_each_drv+0x100/0x1a0 __device_attach+0x174/0x350 device_initial_probe+0x90/0xb0 bus_probe_device+0x4c/0x120 device_add+0xdec/0x116c platform_device_add+0x354/0x598 Remove the assignment of adap->rc to NULL to let cec_delete_adapter() free the allocated rc device after last user of the cec device exits to fix the kmemleak.

Update Linux Kernel to version 6.6.157, Linux Kernel to version 6.12.110, Linux Kernel to version 6.18.51.

Affected: Linux Kernel lt 6.6.143..6.6.157
Linux Kernel lt 6.12.93..6.12.110
Linux Kernel lt 6.18.35..6.18.51
Linux Kernel lt 7.1..7.2.5
Fixed in: Linux Kernel 6.6.157
Linux Kernel 6.12.110
Linux Kernel 6.18.51
Linux Kernel 7.2.5
Linux Kernel 7.3

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Metrics

5.5

Priority

XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

Source: Vendor (CNA), CVSS v3

5.5

CVSS v3

Severity Medium on the scale from 0 to 10.

Source: Debian LTS, Debian, BSI, Msrc Update Guide, CVE.org

0.2 %

EPSS score

Low — model estimates < 1% exploitation likelihood.

Source: FIRST EPSS, percentile 9.8

Show all metrics

Severity: Medium
Priority (0–325) The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first? Read in glossary: 55.66 Methodology
Exploit maturity An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack. Read in glossary: no public PoC known
XIEM Effective CVSS XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command. Read in glossary: 5.5 Methodology
CVSS v3 CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions. Read in glossary: 5.5
EPSS score The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“. Read in glossary: 0.2 %; Low — model estimates < 1% exploitation likelihood.
EPSS percentile The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking. Read in glossary: 9.8; Low — this CVE sits in the lower 10% of all CVEs scored today.
KEV status The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching. Read in glossary: —
Published: 16.09.2026

Detection rules

No NEOSEC detection rule is available for this vulnerability yet.

Classification under NIS2 and CRA

Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

NIS2 NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management. Read in glossary: Handle the vulnerability in regular vulnerability handling under Art. 21(2)(e) NIS2.
CRA The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates. Read in glossary: From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001 ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security. Read in glossary: Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

Description

In the Linux kernel, the following vulnerability has been resolved: media: cec: core: Fix kmemleak due to missed rc_free_device() call The commit dccc0c3ddf8f ("media: rc: fix race between unregister and urb/irq callbacks") removed the implicit call to rc_free_device() from rc_unregister_device(). However, the commit missed to remove the NULL assignment of adap->rc that is now causing rc_free_device() to never be called on an allocated rc device. kmemleak reports following after e.g. dw-hdmi unbind: unreferenced object 0xffff00010ac10000 (size 4096): comm "kworker/u16:1", pid 39, jiffies 4294897739 hex dump (first 32 bytes): 20 23 4b 0a 01 00 ff ff 08 00 c1 0a 01 00 ff ff #K............. 08 00 c1 0a 01 00 ff ff 00 00 00 00 00 00 00 00 ................ backtrace (crc e11baccc): kmemleak_alloc+0x38/0x44 __kmalloc_cache_noprof+0x4a8/0x5e0 rc_allocate_device+0x48/0x2a0 cec_allocate_adapter+0x3ac/0x800 dw_hdmi_cec_probe+0x264/0x634 platform_probe+0xc0/0x188 really_probe+0x4a4/0x8e0 __driver_probe_device+0x2f8/0x440 driver_probe_device+0x60/0x160 __device_attach_driver+0x1a0/0x2a0 bus_for_each_drv+0x100/0x1a0 __device_attach+0x174/0x350 device_initial_probe+0x90/0xb0 bus_probe_device+0x4c/0x120 device_add+0xdec/0x116c platform_device_add+0x354/0x598 Remove the assignment of adap->rc to NULL to let cec_delete_adapter() free the allocated rc device after last user of the cec device exits to fix the kmemleak.

Source: Debian LTS Advisories, Debian Security Advisories, BSI WID Portal, BSI CSAF, Microsoft Security Update Guide, cvelistv5, NVD (NIST)

Affected products
		Affected versions	Fixed in
Linux	Linux	`6.6.143 – < 6.6.157` `7.1 – < 7.2.5` `6.18.35 – < 6.18.51` `—` `6.12.93 – < 6.12.110`	`6.6.157` `7.2.5` `6.18.51` `7.3` `6.12.110`

Vendors and products

Affected operating systems

Linux	debian	linux	`trixie`
Linux	debian	linux-6.12	`bookworm`

References & sources

git.kernel.orgstable/c/954ee95a03b4d31d4505591bfaba02c24b75776b
git.kernel.orgstable/c/f28a8e1ba4d67a18e4662e5acefd5a4389322366
git.kernel.orgstable/c/695063fc57574dd117b1bc750ca189cf03a2caad
git.kernel.orgstable/c/cca2407794795cecff7f8e5f5a79f4ef6b1d6f6c
git.kernel.orgstable/c/a24ba0653f7154e671dc8d2bf64682ab2d042792

Changes to this CVE

Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

19.10.2026Record modifiedLinux

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	added	—	Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/89xxx/CVE-2026-89900.json">CVE-2026-89900</a>

Source identifier: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

16.09.2026ReceivedLinux

Description added or changed

New references:

and 1 more reference

Show 7 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Description	added	—	In the Linux kernel, the following vulnerability has been resolved: media: cec: core: Fix kmemleak due to missed rc_free_device() call The commit dccc0c3ddf8f ("media: rc: fix race between unregister and urb/irq callbacks") removed the implicit call to rc_free_device() from rc_unregister_device(). However, the commit missed to remove the NULL assignment of adap->rc that is now causing rc_free_device() to never be called on an allocated rc device. kmemleak reports following after e.g. dw-hdmi unbind: unreferenced object 0xffff00010ac10000 (size 4096): comm "kworker/u16:1", pid 39, jiffies 4294897739 hex dump (first 32 bytes): 20 23 4b 0a 01 00 ff ff 08 00 c1 0a 01 00 ff ff #K............. 08 00 c1 0a 01 00 ff ff 00 00 00 00 00 00 00 00 ................ backtrace (crc e11baccc): kmemleak_alloc+0x38/0x44 __kmalloc_cache_noprof+0x4a8/0x5e0 rc_allocate_device+0x48/0x2a0 cec_allocate_adapter+0x3ac/0x800 dw_hdmi_cec_probe+0x264/0x634 platform_probe+0xc0/0x188 really_probe+0x4a4/0x8e0 __driver_probe_device+0x2f8/0x440 driver_probe_device+0x60/0x160 __device_attach_driver+0x1a0/0x2a0 bus_for_each_drv+0x100/0x1a0 __device_attach+0x174/0x350 device_initial_probe+0x90/0xb0 bus_probe_device+0x4c/0x120 device_add+0xdec/0x116c platform_device_add+0x354/0x598 Remove the assignment of adap->rc to NULL to let cec_delete_adapter() free the allocated rc device after last user of the cec device exits to fix the kmemleak.
Affected versions (publisher)	added	—	New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/89xxx/CVE-2026-89900.json">CVE-2026-89900</a>
Reference	added	—	https://git.kernel.org/stable/c/695063fc57574dd117b1bc750ca189cf03a2caad
Reference	added	—	https://git.kernel.org/stable/c/954ee95a03b4d31d4505591bfaba02c24b75776b
Reference	added	—	https://git.kernel.org/stable/c/a24ba0653f7154e671dc8d2bf64682ab2d042792
Reference	added	—	https://git.kernel.org/stable/c/cca2407794795cecff7f8e5f5a79f4ef6b1d6f6c
Reference	added	—	https://git.kernel.org/stable/c/f28a8e1ba4d67a18e4662e5acefd5a4389322366