Linux Kernel up to 6.3.1 kheaders kheaders.tar.xz memcpy buffer overflow

CVSS Meta Temp Score
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CTI Interest Score
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7.6$0-$5k0.00

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 6.3.1. This affects the function memcpy of the file /sys/kernel/kheaders.tar.xz of the component kheaders. The manipulation results in buffer overflow. This vulnerability is cataloged as CVE-2023-54056. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.3.1. Affected is the function memcpy of the file /sys/kernel/kheaders.tar.xz of the component kheaders. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: kheaders: Use array declaration instead of char Under CONFIG_FORTIFY_SOURCE, memcpy() will check the size of destination and source buffers. Defining kernel_headers_data as "char" would trip this check. Since these addresses are treated as byte arrays, define them as arrays (as done everywhere else). This was seen with: $ cat /sys/kernel/kheaders.tar.xz >> /dev/null detected buffer overflow in memcpy kernel BUG at lib/string_helpers.c:1027! ... RIP: 0010:fortify_panic+0xf/0x20 [...] Call Trace: <TASK> ikheaders_read+0x45/0x50 [kheaders] kernfs_fop_read_iter+0x1a4/0x2f0 ...

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2023-54056 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 12/30/2025).

The vulnerability scanner Nessus provides a plugin with the ID 279952 (Linux Distros Unpatched Vulnerability : CVE-2023-54056), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.243, 5.10.180, 5.15.111, 6.1.28, 6.2.15 or 6.3.2 eliminates this vulnerability. Applying the patch 719459877d58c8aced5845c1e5b98d8d87d09197/fcd2da2e6bf2640a31a2a5b118b50dc3635c707b/4a07d2d511e2703efd4387891d49e0326f1157f3/b9f6845a492de20679b84bda6b08be347c5819da/d6d1af6b8611801b585c53c0cc63626c8d339e96/82d2e01b95c439fe55fab5e04fc83387c42d3a48/b69edab47f1da8edd8e7bfdf8c70f51a2a5d89fb 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 (279952) and CERT Bund (WID-SEC-2025-2929). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Open Source Linux Kernel

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.0
VulDB Meta Temp Score: 7.6

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 279952
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2023-54056

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.4.243/5.10.180/5.15.111/6.1.28/6.2.15/6.3.2
Patch: 719459877d58c8aced5845c1e5b98d8d87d09197/fcd2da2e6bf2640a31a2a5b118b50dc3635c707b/4a07d2d511e2703efd4387891d49e0326f1157f3/b9f6845a492de20679b84bda6b08be347c5819da/d6d1af6b8611801b585c53c0cc63626c8d339e96/82d2e01b95c439fe55fab5e04fc83387c42d3a48/b69edab47f1da8edd8e7bfdf8c70f51a2a5d89fb

Timelineinfo

12/24/2025 Advisory disclosed
12/24/2025 +0 days CVE reserved
12/24/2025 +0 days VulDB entry created
12/30/2025 +6 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-54056 (🔒)
GCVE (CVE): GCVE-0-2023-54056
GCVE (VulDB): GCVE-100-337944
CERT Bund: WID-SEC-2025-2929 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 12/24/2025 14:19
Updated: 12/30/2025 08:49
Changes: 12/24/2025 14:19 (60), 12/25/2025 14:21 (1), 12/26/2025 01:36 (2), 12/30/2025 08:49 (7)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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