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CVE-2026-23555

CVE-2026-23555 · Xenstored DoS by unprivileged domain

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Any guest issuing a Xenstore command accessing a node using the (illegal) node path "/local/domain/", will crash xenstored due to a clobbered error indicator in xenstored when verifying the node path. Note that the crash is forced via a failing assert() statement in xenstored. In case xenstored is being built with NDEBUG #defined, an unprivileged guest trying to access the node path "/local/domain/" will result in it no longer being serviced by xenstored, other guests (including dom0) will still be serviced, but xenstored will use up all cpu time it can get.

CVSS 7.1 · High · EPSS 0.2% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • xen

    Versions
    • consult Xen advisory XSA-481: Unknown

    No fix published

  • xen Debian:13

    Versions
    • 4.20.0+68-g35cb38b222-1
    • 4.20.2+37-g61ff35323e-0+deb13u1
    • 4.20.2+37-g61ff35323e-1
    • 4.20.2+7-g1badcf5035-0+deb13u1
    • 4.20.2+7-g1badcf5035-1
    • 4.20.2+7-g1badcf5035-2
    Affected ranges
    • ECOSYSTEM: < 4.20.3+127-gc42374a105-0+deb13u1

    Update to 4.20.3+127-gc42374a105-0+deb13u1

  • xen Debian:14

    Versions
    • 4.20.0+68-g35cb38b222-1
    • 4.20.2+37-g61ff35323e-1
    • 4.20.2+7-g1badcf5035-1
    • 4.20.2+7-g1badcf5035-2
    Affected ranges
    • ECOSYSTEM: < 4.20.3+127-gc42374a105-1

    Update to 4.20.3+127-gc42374a105-1

  • xen Ubuntu:16.04:LTS

    Versions
    • 4.5.1-0ubuntu1
    • 4.5.1-0ubuntu2
    • 4.6.0-1ubuntu1
    • 4.6.0-1ubuntu2
    • 4.6.0-1ubuntu4
    • 4.6.0-1ubuntu4.1
    • 4.6.0-1ubuntu4.2
    • 4.6.0-1ubuntu4.3
    • 4.6.5-0ubuntu1
    • 4.6.5-0ubuntu1.1
    • 4.6.5-0ubuntu1.2
    • 4.6.5-0ubuntu1.4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • xen Ubuntu:18.04:LTS

    Versions
    • 4.9.0-0ubuntu3
    • 4.9.0-0ubuntu4
    • 4.9.2-0ubuntu1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • xen Ubuntu:20.04:LTS

    Versions
    • 4.9.2-0ubuntu2
    • 4.9.2-0ubuntu6
    • 4.9.2-0ubuntu7
    • 4.11.3+24-g14b62ab3e5-1ubuntu1
    • 4.11.3+24-g14b62ab3e5-1ubuntu2
    • 4.11.3+24-g14b62ab3e5-1ubuntu2.2
    • 4.11.3+24-g14b62ab3e5-1ubuntu2.3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • xen Ubuntu:22.04:LTS

    Versions
    • 4.11.4+24-gddaaccbbab-1ubuntu2
    • 4.16.0-1~ubuntu2
    • 4.16.0-1~ubuntu2.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • xen Ubuntu:24.04:LTS

    Versions
    • 4.17.2-1
    • 4.17.2+55-g0b56bed864-1
    • 4.17.2+76-ge1f9cb16e2-1
    • 4.17.2+76-ge1f9cb16e2-1ubuntu1
    • 4.17.3+10-g091466ba55-1
    • 4.17.3+10-g091466ba55-1.1ubuntu2
    • 4.17.3+10-g091466ba55-1.1ubuntu3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • xen Ubuntu:25.10

    Versions
    • 4.20.0-1ubuntu1
    • 4.20.0+68-g35cb38b222-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • xen Ubuntu:26.10

    Versions
    • 4.20.2+7-g1badcf5035-2build2
    • 4.20.2+37-g61ff35323e-1ubuntu1
    • 4.20.3+127-gc42374a105-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • xen Ubuntu:26.04:LTS

    Versions
    • 4.20.0+68-g35cb38b222-1
    • 4.20.2+7-g1badcf5035-2
    • 4.20.2+7-g1badcf5035-2build2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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