CVE-2025-21897 Vulnerability Analysis & Exploit Details

CVE-2025-21897
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-2025-21897 Details

Status: Awaiting Analysis

Published on: 01 Apr 2025, 16:15 UTC

CVSS Release:

CVE-2025-21897 Vulnerability Summary

CVE-2025-21897: In the Linux kernel, the following vulnerability has been resolved: sched_ext: Fix pick_task_scx() picking non-queued tasks when it's called without balance() a6250aa251ea ("sched_ext: Handle cases where pick_task_scx() is called without preceding balance_scx()") added a workaround to handle the cases where pick_task_scx() is called without prececing balance_scx() which is due to a fair class bug where pick_taks_fair() may return NULL after a true return from balance_fair(). The workaround detects when pick_task_scx() is called without preceding balance_scx() and emulates SCX_RQ_BAL_KEEP and triggers kicking to avoid stalling. Unfortunately, the workaround code was testing whether @prev was on SCX to decide whether to keep the task running. This is incorrect as the task may be on SCX but no longer runnable. This could lead to a non-runnable task to be returned from pick_task_scx() which cause interesting confusions and failures. e.g. A common failure mode is the task ending up with (!on_rq && on_cpu) state which can cause potential wakers to busy loop, which can easily lead to deadlocks. Fix it by testing whether @prev has SCX_TASK_QUEUED set. This makes @prev_on_scx only used in one place. Open code the usage and improve the comment while at it.

Assessing the Risk of CVE-2025-21897

Access Complexity Graph

The exploitability of CVE-2025-21897 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-2025-21897

No exploitability data is available for CVE-2025-21897.

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-2025-21897, 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-2025-21897, showing how Confidentiality, Integrity, and Availability might be affected if the vulnerability is exploited. Higher values usually signal greater potential damage.

  • Confidentiality: None
    CVE-2025-21897 does not compromise confidentiality.
  • Integrity: None
    CVE-2025-21897 does not impact data integrity.
  • Availability: None
    CVE-2025-21897 does not affect system availability.

CVE-2025-21897 References

External References

CWE Common Weakness Enumeration

Unknown

Protect Your Infrastructure against CVE-2025-21897: 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-2025-3800 – A vulnerability has been found in WCMS 11 and classified as critical. Affected by this vulnerability is an unknown functionality of the file app/co...
  • CVE-2025-3799 – A vulnerability, which was classified as critical, was found in WCMS 11. Affected is an unknown function of the file app/controllers/AnonymousContr...
  • CVE-2025-3798 – A vulnerability, which was classified as critical, has been found in WCMS 11. This issue affects the function sub of the file app/admin/AdvadminCon...
  • CVE-2025-3661 – The SB Chart block plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘className’ parameter in all versions up to, and inclu...
  • CVE-2025-3404 – The Download Manager plugin for WordPress is vulnerable to arbitrary file deletion due to insufficient file path validation in the savePackage func...