An issue was discovered in the Linux kernel 5.5 through 5.7.9, as used in Xen through 4.13.x for x86 PV guests. An attacker may be granted the I/O port permissions of an unrelated task. This occurs because tss_invalidate_io_bitmap mishandling causes a loss of synchronization between the I/O bitmaps of TSS and Xen, aka CID-cadfad870154.

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-004097 advisory.

    An issue was discovered in the Linux kernel 5.5 through 5.7.9, as used in Xen through 4.13.x for x86 PV     guests. An attacker may be granted the I/O port permissions of an unrelated task. This occurs because     tss_invalidate_io_bitmap mishandling causes a loss of synchronization between the I/O bitmaps of TSS and     Xen, aka CID-cadfad870154.

Tenable has extracted the preceding description block directly from the Unity Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-004308 advisory.

    An issue was discovered in the Linux kernel 5.5 through 5.7.9, as used in Xen through 4.13.x for x86 PV     guests. An attacker may be granted the I/O port permissions of an unrelated task. This occurs because     tss_invalidate_io_bitmap mishandling causes a loss of synchronization between the I/O bitmaps of TSS and     Xen, aka CID-cadfad870154.

Tenable has extracted the preceding description block directly from the Unity Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - An issue was discovered in the Linux kernel 5.5 through 5.7.9, as used in Xen through 4.13.x for x86 PV     guests. An attacker may be granted the I/O port permissions of an unrelated task. This occurs because     tss_invalidate_io_bitmap mishandling causes a loss of synchronization between the I/O bitmaps of TSS and     Xen, aka CID-cadfad870154. (CVE-2020-15852)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Severity
288799	Unity Linux 20.1060a / 20.1070a Security Update: kernel (UTSA-2026-004097)	Nessus	Unity Linux Local Security Checks	high
288434	Unity Linux 20.1060e / 20.1070e Security Update: kernel (UTSA-2026-004308)	Nessus	Unity Linux Local Security Checks	high
246734	Linux Distros Unpatched Vulnerability : CVE-2020-15852	Nessus	Misc.	high

Detections

Analytics

CVE-2020-15852

high

Tenable Plugins

high

high

high