ZeroDay Findings
Sign inSign up

Every 4 hours

Cyber

Keywords match words in the title. Separate terms with spaces.

  1. Oct 16, 2026 · CSO Online

    Critical Vulnerability in Linux Kernel Allows VM Escape

    A severe flaw in the Linux kernel has been patched, preventing potential guest-to-host escape attacks that could compromise system integrity.

    What changed

    The Linux kernel has been updated to address a critical vulnerability tracked as CVE-2026-99999, which allowed attackers to escape from a virtual machine (VM) to the underlying host. This flaw, known as PwnEscape, involved manipulating packet metadata to alter an IPv4 header after processing, potentially leading to host-level code execution.

    • The vulnerability was discovered during Vercel’s Sandbox security challenge.
    • The issue was classified as the most severe finding reported in the challenge.
    • The flaw has now been resolved with multiple stable-branch fixes released.

    Who is affected

    Organizations utilizing affected versions of the Linux kernel in their virtualized environments may be at risk. The vulnerability primarily impacts those running specific kernel versions.

    • Users of Linux kernel versions 5.10, 5.15, 6.1, 6.6, 6.12, 6.18, and 7.2.
    • Cloud service providers using virtualization technologies based on the Linux kernel.
    • Developers and researchers participating in sandbox environments like Vercel's.

    What to do

    It is imperative for affected organizations to update their Linux kernel to the latest patched versions to mitigate the risk associated with this vulnerability. Regular monitoring for security updates and vulnerabilities is also recommended.

    • Upgrade to the latest stable versions of the Linux kernel as specified in the NVD.
    • Review and enhance security measures for virtualized environments.
    • Stay informed about future vulnerabilities and participate in security challenges to test system defenses.

    Original report

  2. Oct 16, 2026 · Security Affairs

    Critical Atlassian Flaw Added to CISA's Exploited Vulnerabilities Catalog

    CISA has included a critical vulnerability in Atlassian products in its Known Exploited Vulnerabilities catalog, highlighting an ongoing threat to users.

    What changed

    The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has officially added a critical vulnerability in Atlassian products, identified as CVE-2026-21589, to its Known Exploited Vulnerabilities (KEV) catalog. This vulnerability has a CVSS score of 9.3, indicating its severity.

    Exploitation of this flaw began in early October, prompting immediate attention from security professionals and organizations using Atlassian software.

    Who is affected

    Organizations utilizing Atlassian products are at risk due to this vulnerability. This includes a wide range of users from various sectors, making it a significant concern for many.

    The following groups are particularly impacted:

    • Users of Atlassian Jira Software
    • Users of Atlassian Confluence
    • Organizations in the technology and project management sectors
    • Any entity relying on Atlassian tools for collaboration and project tracking

    What to do

    Security teams should prioritize assessing their exposure to CVE-2026-21589 and take immediate action to mitigate risks. It is crucial to implement any available patches or updates provided by Atlassian.

    Additionally, organizations should monitor their systems for any signs of exploitation and enhance their security posture accordingly.

    • Review and apply security updates from Atlassian as soon as possible.
    • Conduct a thorough assessment of systems for potential exploitation.
    • Enhance monitoring for unusual activity related to Atlassian products.
    • Stay informed about further developments regarding this vulnerability through CISA and other security advisories.

    Original report