CVE-2026-99207 Vulnerability Analysis & Exploit Details

CVE-2026-99207
Vulnerability Scoring

Analysis In Progress
Analysis In Progress

Attack Complexity Details

  • Attack Complexity:
    Attack Complexity Analysis In Progress
  • Attack Vector:
    Attack Vector Under Analysis
  • Privileges Required: None
    No authentication is required for exploitation.
  • Scope:
    Impact is confined to the initially vulnerable component.
  • User Interaction: None
    No user interaction is necessary for exploitation.

CVE-2026-99207 Details

Status: Received on 28 Oct 2026, 11:17 UTC

Published on: 28 Oct 2026, 11:17 UTC

CVSS Release:

CVE-2026-99207 Vulnerability Summary

CVE-2026-99207: In the Linux kernel, the following vulnerability has been resolved: scsi: target: Disable interrupts while holding delayed_cmd_lock target_do_delayed_work() takes dev->delayed_cmd_lock with a plain spin_lock(). It runs from system_percpu_wq, so interrupts stay enabled while the lock is held. Every other acquisition of that lock uses spin_lock_irqsave(): target_handle_task_attr() and transport_complete_ordered_sync() in target_core_transport.c, and target_non_ordered_release() in target_core_device.c. That was safe while every caller of transport_complete_task_attr() ran in process context: target_complete_ok_work() from target_completion_wq, transport_complete_qf() from dev->qf_work_queue, and transport_generic_request_failure() from the submit and execute paths. Since commit 06933066d88a ("scsi: target: Add support for completing commands from backend context") that is no longer true. With complete_type=1 on a fabric that sets direct_compl_supp, target_complete() runs target_complete_ok_work() inline in the backend's completion context, which target_complete_cmd_with_sense() documents as "May be called from interrupt context". For iblock that is the bio end_io. target_complete_ok_work() starts with transport_complete_task_attr(), which takes delayed_cmd_lock in two ways: - Every ORDERED command is put on dev->delayed_cmd_list by target_handle_task_attr() and dispatched from there by target_do_delayed_work(), which marks it SCF_TASK_ORDERED_SYNC. Its completion therefore goes through transport_complete_ordered_sync(). - A SIMPLE command that completes while an ORDERED command is pending drops the last reference to the killed dev->non_ordered, and percpu_ref_put() then runs target_non_ordered_release() in the completing context. Both take the lock and, if commands are waiting, call schedule_work(&dev->delayed_cmd_work), which queues on system_percpu_wq, i.e. on the CPU that took the completion. Further completions for the same queue are typically delivered there too, so one arriving while the work holds the lock spins on it forever. Reaching this needs complete_type=1, which is not the default (vhost-scsi, the only fabric with direct_compl_supp, defaults to TARGET_QUEUE_COMPL), a backend whose I/O completes from interrupt context, and ORDERED commands from the initiator. Linux virtio_scsi guests send only VIRTIO_SCSI_S_SIMPLE and never take the ordered path; any guest that uses the ORDERED task attribute, which vhost-scsi accepts, does. target_do_delayed_work() is a work item and always runs in process context, so spin_lock_irq() is sufficient. Found by inspection; no runtime report. A single ORDERED command goes through both acquisitions, so with CONFIG_PROVE_LOCKING the first one completed through direct completion should produce an inconsistent lock state report on delayed_cmd_lock (hardirq or softirq, depending on where the backend completes).

Assessing the Risk of CVE-2026-99207

Access Complexity Graph

The exploitability of CVE-2026-99207 depends on two key factors: attack complexity (the level of effort required to execute an exploit) and privileges required (the access level an attacker needs).

Exploitability Analysis for CVE-2026-99207

No exploitability data is available for CVE-2026-99207.

Understanding AC and PR

A lower complexity and fewer privilege requirements make exploitation easier. Security teams should evaluate these aspects to determine the urgency of mitigation strategies, such as patch management and access control policies.

Attack Complexity (AC) measures the difficulty in executing an exploit. A high AC means that specific conditions must be met, making an attack more challenging, while a low AC means the vulnerability can be exploited with minimal effort.

Privileges Required (PR) determine the level of system access necessary for an attack. Vulnerabilities requiring no privileges are more accessible to attackers, whereas high privilege requirements limit exploitation to authorized users with elevated access.

CVSS Score Breakdown Chart

Above is the CVSS Sub-score Breakdown for CVE-2026-99207, illustrating how Base, Impact, and Exploitability factors combine to form the overall severity rating. A higher sub-score typically indicates a more severe or easier-to-exploit vulnerability.

CIA Impact Analysis

Below is the Impact Analysis for CVE-2026-99207, showing how Confidentiality, Integrity, and Availability might be affected if the vulnerability is exploited. Higher values usually signal greater potential damage.

  • Confidentiality: None
    CVE-2026-99207 does not compromise confidentiality.
  • Integrity: None
    CVE-2026-99207 does not impact data integrity.
  • Availability: None
    CVE-2026-99207 does not affect system availability.

CVE-2026-99207 References

External References

CWE Common Weakness Enumeration

Unknown

Protect Your Infrastructure against CVE-2026-99207: Combat Critical CVE Threats

Stay updated with real-time CVE vulnerabilities and take action to secure your systems. Enhance your cybersecurity posture with the latest threat intelligence and mitigation techniques. Develop the skills necessary to defend against CVEs and secure critical infrastructures. Join the top cybersecurity professionals safeguarding today's infrastructures.

Other 5 Recently Published CVEs Vulnerabilities

  • CVE-2026-93516 – A use-after-free caused by lack of lifecycle management when adding / removing XInput master devices in X.org X Server before 21.1.25 and XWayland ...
  • CVE-2026-93515 – A use-after-free in present_clear_window_notifies() in the X.org X Server before 21.1.25 and X Wayland before 24.1.14 could be used by malicious X...
  • CVE-2026-67080 – HCL BigFix AEX is affected by an Information Disclosure vulnerability due to improper handling of errors or exceptional conditions. This could allo...
  • CVE-2026-67079 – HCL BigFix AEX is affected by a Clickjacking vulnerability, which could allow an attacker to embed the application within a malicious web page or i...
  • CVE-2026-67077 – HCL BigFix AEX is affected by a Server-Side Request Forgery vulnerability, which could allow an attacker to cause the application to send unauthori...