Linux Kernel up to 6.1.52/6.4.15/6.5.2 enc_dec_hypercall privilege escalation

Summaryinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.1.52/6.4.15/6.5.2. Affected is the function enc_dec_hypercall. The manipulation results in an unknown weakness. This vulnerability is reported as CVE-2023-53996. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.52/6.4.15/6.5.2. It has been classified as critical. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: x86/sev: Make enc_dec_hypercall() accept a size instead of npages enc_dec_hypercall() accepted a page count instead of a size, which forced its callers to round up. As a result, non-page aligned vaddrs caused pages to be spuriously marked as decrypted via the encryption status hypercall, which in turn caused consistent corruption of pages during live migration. Live migration requires accurate encryption status information to avoid migrating pages from the wrong perspective.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2023-53996 since 12/24/2025. The exploitability is told to be easy. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 02/25/2026).

The vulnerability scanner Nessus provides a plugin with the ID 279961 (Linux Distros Unpatched Vulnerability : CVE-2023-53996), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.53, 6.4.16 or 6.5.3 eliminates this vulnerability. Applying the patch ba50e7773a99a109a1ea6f753b766a080d3b21cc/6615212d8e131b45bd9705b0d69cc0d2f624666f/8ae7457e71a320867d868f2622d7c643596e4f43/ac3f9c9f1b37edaa7d1a9b908bc79d843955a1a2 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (279961) and CERT Bund (WID-SEC-2025-2920). Once again VulDB remains the best source for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.1.24
• 6.1.25
• 6.1.26
• 6.1.27
• 6.1.28
• 6.1.29
• 6.1.30
• 6.1.31
• 6.1.32
• 6.1.33
• 6.1.34
• 6.1.35
• 6.1.36
• 6.1.37
• 6.1.38
• 6.1.39
• 6.1.40
• 6.1.41
• 6.1.42
• 6.1.43
• 6.1.44
• 6.1.45
• 6.1.46
• 6.1.47
• 6.1.48
• 6.1.49
• 6.1.50
• 6.1.51
• 6.1.52
• 6.4.0
• 6.4.1
• 6.4.2
• 6.4.3
• 6.4.4
• 6.4.5
• 6.4.6
• 6.4.7
• 6.4.8
• 6.4.9
• 6.4.10
• 6.4.11
• 6.4.12
• 6.4.13
• 6.4.14
• 6.4.15
• 6.5.0
• 6.5.1
• 6.5.2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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