# CVE-2026-17523: Linux Kernel local privilege escalation in CAN BCM

Source: https://junglewise.ai/threats/cve-2026-17523-linux-kernel-local-privilege-escalation-in-can-bcm  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-27. Updated: 2026-07-27  
License: CC BY 4.0 with a link back

CVE-2026-17523 · Severity: high · CVSS 7.8 · Published 2026-07-27

A security vulnerability has been identified in the Linux kernel's CAN Broadcast Manager (BCM) component. This flaw allows a standard user with limited access to execute malicious code with the highest level of system privileges (root). An attacker who successfully exploits this can take full control of the affected system, potentially leading to data theft or complete service disruption.

Technologies: [Red Hat Enterprise Linux 8](https://junglewise.ai/threats/technologies/enterprise-linux-8). Vendors: [Red Hat](https://junglewise.ai/threats/vendors/red-hat).

## Quick answers

**Is CVE-2026-17523 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-17523 being exploited in the wild.

**How severe is CVE-2026-17523?** High severity, with a CVSS score of 7.8, published 27 July 2026.

**Which products and versions are affected?** Red Hat Enterprise Linux 8 All versions.

**Is there a fix for CVE-2026-17523?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-17523 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2026-17523?** Check whether you run Red Hat Enterprise Linux 8 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A flaw was discovered in the Linux kernel's Controller Area Network (CAN) Broadcast Manager (BCM) implementation. The vulnerability is classified as an expired pointer dereference (CWE-825) within the bcm_op runtime updates. An unprivileged local attacker can exploit this race condition or improper locking mechanism to trigger arbitrary kernel code execution. While a Proof of Concept (PoC) exists that utilizes unprivileged user namespaces and the kernel-modules-extra package, the underlying vulnerability is reachable without these specific configurations. Successful exploitation results in local privilege escalation (LPE) to root. Fixes involve switching timers to HRTIMER_MODE_SOFT and implementing proper locking for runtime updates.

## Affected products

- Red Hat Red Hat Enterprise Linux 8 All versions

## Timeline

- 2026-07-27: disclosed: Vulnerability reported and published in NVD/Red Hat Bugzilla

## References

- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)
- [https://access.redhat.com/security/cve/CVE-2026-17523](https://access.redhat.com/security/cve/CVE-2026-17523)
- [https://bugzilla.redhat.com/show_bug.cgi?id=2507407](https://bugzilla.redhat.com/show_bug.cgi?id=2507407)
- [https://github.com/torvalds/linux/commit/bf74aa86e111aa3b2fbb25db37e3a3fab71b5b68](https://github.com/torvalds/linux/commit/bf74aa86e111aa3b2fbb25db37e3a3fab71b5b68)

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