Microsoft addresses 167 CVEs in its largest Patch Tuesday to date, including three zero-day vulnerabilities, two of which were exploited in the wild.

Microsoft’s October 2025 Patch Tuesday Addresses 167 CVEs (CVE-2025-24990, CVE-2025-59230)

Improper access control in Windows Remote Access Connection Manager allows an authorized attacker to elevate privileges locally.

The remote Windows host is missing security update 5066782. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

  - In IGEL OS before 11, Secure Boot can be bypassed because the igel-flash-driver module improperly verifies     a cryptographic signature. Ultimately, a crafted root filesystem can be mounted from an unverified     SquashFS image. (CVE-2025-47827)

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

The remote Windows host is missing security update 5066793. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

  - TCG TPM2.0 Reference implementation's CryptHmacSign helper function is vulnerable to Out-of-Bounds read     due to the lack of validation the signature scheme with the signature key's algorithm. See Errata Revision     1.83 and advisory TCGVRT0009 for TCG standard TPM2.0 (CVE-2025-2884)

  - In IGEL OS before 11, Secure Boot can be bypassed because the igel-flash-driver module improperly verifies     a cryptographic signature. Ultimately, a crafted root filesystem can be mounted from an unverified     SquashFS image. (CVE-2025-47827)

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

The remote Windows host is missing security update 5066876. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

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

The remote Windows host is missing security update 5066836. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

  - In IGEL OS before 11, Secure Boot can be bypassed because the igel-flash-driver module improperly verifies     a cryptographic signature. Ultimately, a crafted root filesystem can be mounted from an unverified     SquashFS image. (CVE-2025-47827)

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

The remote Windows host is missing security update 5066877. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

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

The remote Windows host is missing security update 5066791. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

  - In IGEL OS before 11, Secure Boot can be bypassed because the igel-flash-driver module improperly verifies     a cryptographic signature. Ultimately, a crafted root filesystem can be mounted from an unverified     SquashFS image. (CVE-2025-47827)

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

The remote Windows host is missing security update 5066586. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

  - In IGEL OS before 11, Secure Boot can be bypassed because the igel-flash-driver module improperly verifies     a cryptographic signature. Ultimately, a crafted root filesystem can be mounted from an unverified     SquashFS image. (CVE-2025-47827)

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

The remote Windows host is missing security update 5066780. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

  - TCG TPM2.0 Reference implementation's CryptHmacSign helper function is vulnerable to Out-of-Bounds read     due to the lack of validation the signature scheme with the signature key's algorithm. See Errata Revision     1.83 and advisory TCGVRT0009 for TCG standard TPM2.0 (CVE-2025-2884)

  - In IGEL OS before 11, Secure Boot can be bypassed because the igel-flash-driver module improperly verifies     a cryptographic signature. Ultimately, a crafted root filesystem can be mounted from an unverified     SquashFS image. (CVE-2025-47827)

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

The remote Windows host is missing security update 5066874. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

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

The remote Windows host is missing security update 5066835. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

  - TCG TPM2.0 Reference implementation's CryptHmacSign helper function is vulnerable to Out-of-Bounds read     due to the lack of validation the signature scheme with the signature key's algorithm. See Errata Revision     1.83 and advisory TCGVRT0009 for TCG standard TPM2.0 (CVE-2025-2884)

  - In IGEL OS before 11, Secure Boot can be bypassed because the igel-flash-driver module improperly verifies     a cryptographic signature. Ultimately, a crafted root filesystem can be mounted from an unverified     SquashFS image. (CVE-2025-47827)

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

The remote Windows host is missing security update 5066873. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

  - In IGEL OS before 11, Secure Boot can be bypassed because the igel-flash-driver module improperly verifies     a cryptographic signature. Ultimately, a crafted root filesystem can be mounted from an unverified     SquashFS image. (CVE-2025-47827)

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

The remote Windows host is missing security update 5066875. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

  - In IGEL OS before 11, Secure Boot can be bypassed because the igel-flash-driver module improperly verifies     a cryptographic signature. Ultimately, a crafted root filesystem can be mounted from an unverified     SquashFS image. (CVE-2025-47827)

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

The remote Windows host is missing security update 5066837. It is, therefore, affected by multiple vulnerabilities

  - tif_predict.h and tif_predict.c in libtiff 4.0.6 have assertions that can lead to assertion failures in     debug mode, or buffer overflows in release mode, when dealing with unusual tile size like YCbCr with     subsampling. Reported as MSVR 35105, aka Predictor heap-buffer-overflow. (CVE-2016-9535)

  - In IGEL OS before 11, Secure Boot can be bypassed because the igel-flash-driver module improperly verifies     a cryptographic signature. Ultimately, a crafted root filesystem can be mounted from an unverified     SquashFS image. (CVE-2025-47827)

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

ID	Name	Product	Family	Severity
270390	KB5066782: Windows Server 2022 / Azure Stack HCI 22H2 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270386	KB5066793: Windows 11 version 22H2 / Windows 11 version 23H2 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270385	KB5066876: Windows Server 2008 R2 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270384	KB5066836: Windows 10 Version 1607 / Windows Server 2016 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270381	KB5066877: Windows Server 2008 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270379	KB5066791: Windows 10 version 21H2 / Windows 10 Version 22H2 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270378	KB5066586: Windows 10 version 1809 / Windows Server 2019 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270377	KB5066780: Windows 11 version 22H2 / Windows Server version 23H2 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270375	KB5066874: Windows Server 2008 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270371	KB5066835: Windows 11 Version 24H2 / Windows Server 2025 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270367	KB5066873: Windows Server 2012 R2 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270366	KB5066875: Windows Server 2012 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical
270365	KB5066837: Windows 10 LTS 1507 Security Update (October 2025)	Nessus	Windows : Microsoft Bulletins	critical

Detections

Analytics

CVE-2025-59230

high

Tenable Plugins

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical