CVE-2023-6779

Memory Safety in Fedoraproject Fedora 38 … 39

Public PoCMemory Safety

Published

31 January 2024

Modified

12 May 2026

CVSS Score v3.1 8.2

Click a component to see what it means

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

EPSS Score 0.032 88th percentile

Risk Priority 66 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-6779 is a high-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Fedoraproject Fedora. Its CVSS base score is 8.2 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data Obfuscation (T1001); ranked in the top 12% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

EU & UK References

🇪🇺 ENISA EUVD: EUVD-2023-58991

Vulnerability Data

An off-by-one heap-based buffer overflow was found in the __vsyslog_internal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when these functions are called with a message bigger than INT_MAX bytes,…

leading to an incorrect calculation of the buffer size to store the message, resulting in an application crash. This issue affects glibc 2.37 and newer.

CWE(s): CWE-122 CWE-787

Related Threats

MITRE ATT&CK Enterprise Techniques

T1001 Data Obfuscation Command And Control

Adversaries may obfuscate command and control traffic to make it more difficult to detect.

attack.mitre.org →

T1001.002 Steganography Command And Control

Adversaries may use steganographic techniques to hide command and control traffic to make detection efforts more difficult.

attack.mitre.org →

T1003.001 LSASS Memory Credential Access

Adversaries may attempt to access credential material stored in the process memory of the Local Security Authority Subsystem Service (LSASS).

attack.mitre.org →

T1003.002 Security Account Manager Credential Access

Adversaries may attempt to extract credential material from the Security Account Manager (SAM) database either through in-memory techniques or through the Windows Registry where the SAM database is stored.

attack.mitre.org →

T1003.004 LSA Secrets Credential Access

Adversaries with SYSTEM access to a host may attempt to access Local Security Authority (LSA) secrets, which can contain a variety of different credential materials, such as credentials for service accounts.

attack.mitre.org →

T1003.006 DCSync Credential Access

Adversaries may attempt to access credentials and other sensitive information by abusing a Windows Domain Controller's application programming interface (API)(Citation: Microsoft DRSR Dec 2017) (Citation: Microsoft GetNCCChanges) (Citati…

attack.mitre.org →

Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-6246Same product: Fedoraproject Fedora

CVE-2023-5686Same product: Fedoraproject Fedora

CVE-2024-21795Same product: Fedoraproject Fedora

CVE-2024-24246Same product: Fedoraproject Fedora

CVE-2024-5835Same product: Fedoraproject Fedora

CVE-2023-5344Same product: Fedoraproject Fedora

CVE-2023-4016Same product: Fedoraproject Fedora

CVE-2024-4559Same product: Fedoraproject Fedora

CVE-2024-3516Same product: Fedoraproject Fedora

CVE-2023-4322Same product: Fedoraproject Fedora

Affected Assets

gnu

glibc

2.37 — 2.39

fedoraproject

fedora

38, 39

Mitigating Controls

Control response

Prevent

Stop it (NIST 800-53)

—

Detect

Catch it (NIST detect / respond)

—

Harden

Shrink the surface (DISA STIG)

—

Validate

Prove the fix (OWASP ASVS)

V1.4.1

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation (including fuzzing and memory-error detectors) can discover heap overflows after they have been coded.

SI-10 Information Input Validation good match

Input validation enforces bounds checking on data written to heap buffers, directly stopping the overflow condition from being introduced.

SA-15 Development Process, Standards, and Tools partial match

Requiring documented secure-development standards and tools can mandate bounds-checked coding practices that avoid the weakness.

SA-8 Security and Privacy Engineering Principles partial match

Security engineering principles require use of memory-safe constructs and bounds-checked allocation routines that avoid introducing heap overflows.

SI-16 Memory Protection partial match

Memory-protection mechanisms limit the ability of a heap overflow to execute attacker-controlled code or corrupt adjacent structures.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

ID.RA-01 partial match

blocks

Vulnerability scanning and recording can discover heap-overflow flaws but does not prevent their introduction in code.

PR.PS-02 partial match

blocks

Timely patching removes known heap-overflow instances after they exist.

PR.PS-06 partial match

blocks

Secure-development practices directly require bounds checking and safe memory handling that prevent heap overflows.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.14 Information transfer partial match

removes

A.5.15 Access control partial match

removes

A.5.16 Identity management partial match

removes

A.5.17 Authentication information partial match

removes

A.5.18 Access rights partial match

removes

A.7.2 Physical entry partial match

removes