Linux Kernel up to 7.0-rc2 ucan ucan_read_bulk_callback length infinite loop

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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability has been found in Linux Kernel up to 7.0-rc2 and classified as critical. This issue affects the function ucan_read_bulk_callback of the component ucan. The manipulation of the argument length leads to infinite loop. This vulnerability is uniquely identified as CVE-2026-23298. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 7.0-rc2. This issue affects the function ucan_read_bulk_callback of the component ucan. The manipulation of the argument length 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: can: ucan: Fix infinite loop from zero-length messages If a broken ucan device gets a message with the message length field set to 0, then the driver will loop for forever in ucan_read_bulk_callback(), hanging the system. If the length is 0, just skip the message and go on to the next one. This has been fixed in the kvaser_usb driver in the past in commit 0c73772cd2b8 ("can: kvaser_usb: leaf: Fix potential infinite loop in command parsers"), so there must be some broken devices out there like this somewhere.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2026-23298 since 01/13/2026. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 311783 (Debian dla-4561 : linux-config-6.1 - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.167, 6.6.130, 6.12.77, 6.18.17, 6.19.7 or 7.0-rc3 eliminates this vulnerability. Applying the patch ab6f075492d37368b4c7b0df7f7fdc2b666887fc/13b646eec3ba1131180803f5aaf1fee23540ad8f/bd85f21a6219aeae4389d700c54f1799f4b814e0/aa9e0a7fe5efc2f74327fd37d828e9a51d9ff588/c7bc62be6c1a60bb21301692009590b1ffda91d9/1e446fd0582ad8be9f6dafb115fc2e7245f9bea7 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (311783) and CERT Bund (WID-SEC-2026-0861). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Google Cloud Platform
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • RESF Rocky Linux
  • F5 BIG-IP

Productinfo

Type

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Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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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

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 311783
Nessus Name: Debian dla-4561 : linux-config-6.1 - security update

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.1.167/6.6.130/6.12.77/6.18.17/6.19.7/7.0-rc3
Patch: ab6f075492d37368b4c7b0df7f7fdc2b666887fc/13b646eec3ba1131180803f5aaf1fee23540ad8f/bd85f21a6219aeae4389d700c54f1799f4b814e0/aa9e0a7fe5efc2f74327fd37d828e9a51d9ff588/c7bc62be6c1a60bb21301692009590b1ffda91d9/1e446fd0582ad8be9f6dafb115fc2e7245f9bea7

Timelineinfo

01/13/2026 CVE reserved
03/25/2026 +71 days Advisory disclosed
03/25/2026 +0 days VulDB entry created
07/02/2026 +98 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-23298 (🔒)
GCVE (CVE): GCVE-0-2026-23298
GCVE (VulDB): GCVE-100-353027
CERT Bund: WID-SEC-2026-0861 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 03/25/2026 12:54
Updated: 07/02/2026 01:46
Changes: 03/25/2026 12:54 (60), 03/26/2026 03:49 (7), 03/30/2026 00:43 (1), 05/04/2026 00:45 (2), 06/01/2026 01:20 (10), 06/16/2026 16:41 (1), 07/02/2026 01:46 (1)
Complete: 🔍
Cache ID: 216::103

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