Cyber Resilience

CVE-2023-4194

Memory Safety in Linux Kernel ≤ 6.4

Published
07 August 2023
Modified
24 March 2026
Patch / advisory
CVSS Score v3.1 5.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
EPSS Score 0.0027 20th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2023-4194 is a medium-severity Type Confusion (CWE-843) vulnerability in Linux Linux Kernel. Its CVSS base score is 5.5 (Medium).

Operationally, ranked at the 20th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A flaw was found in the Linux kernel's TUN/TAP functionality. This issue could allow a local user to bypass network filters and gain unauthorized access to some resources. The original patches fixing CVE-2023-1076 are incorrect or incomplete. The problem is…

more

that the following upstream commits - a096ccca6e50 ("tun: tun_chr_open(): correctly initialize socket uid"), - 66b2c338adce ("tap: tap_open(): correctly initialize socket uid"), pass "inode->i_uid" to sock_init_data_uid() as the last parameter and that turns out to not be accurate.

CWE(s)

Related Threats

CVEs Like This One

CVE-2023-2156Same product: Debian Debian Linux
CVE-2024-1151Same product: Debian Debian Linux
CVE-2023-42756Same product: Debian Debian Linux
CVE-2023-3773Same product: Debian Debian Linux
CVE-2023-4132Same product: Debian Debian Linux
CVE-2023-3772Same product: Debian Debian Linux
CVE-2024-26994Same product: Debian Debian Linux
CVE-2023-1073Same product: Fedoraproject Fedora
CVE-2023-4155Same product: Fedoraproject Fedora
CVE-2024-0607Same product: Fedoraproject Fedora

Affected Assets

linux
linux kernel
6.5 · ≤ 6.4
redhat
enterprise linux
8.0, 9.0
fedoraproject
fedora
37, 38
debian
debian linux
10.0, 11.0, 12.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V1.5.2
  • V3.2.3
  • V15.3.5

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-863

Periodic review and update of procedures reduces incorrect authorization implementations over time.

addresses: CWE-863

Supervision identifies cases where authorization logic incorrectly permits unauthorized actions.

addresses: CWE-863

Defining permitted attribute values and auditing modifications reduces the chance of incorrect authorization outcomes due to tampered or missing labels.

addresses: CWE-863

The authorization process and usage restrictions help prevent incorrect authorization for remote access types.

addresses: CWE-863

Establishing configuration and connection requirements helps ensure correct rather than incorrect authorization for wireless access.

addresses: CWE-863

Establishing connection authorization processes for mobile devices helps ensure authorization decisions are correctly implemented rather than incorrect.

addresses: CWE-863

Monitoring account use, notifying on changes, and reviewing accounts for compliance corrects incorrect authorization assignments.

addresses: CWE-863

Ensures authorization decisions for external system use are correctly implemented and enforced.

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.

PR.AA-05 mostly match
prevents

Defining, enforcing, and reviewing access authorizations and least privilege directly prevents incorrect authorization checks.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly prevent type-confusion flaws via safe typing, static analysis, and code review while the control itself addresses many additional weaknesses.

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.

detects

Security testing in development can detect type-confusion vulnerabilities through fuzzing and static analysis.

prevents

Requiring consistency between access rights and classification plus formal approval steps ensures that the authorization logic correctly distinguishes between entities that should and should not be granted access.

prevents

Enforcing policy-driven approval and role-change reviews stops incorrect or stale authorization decisions from remaining in effect after job changes or terminations.

prevents

Secure SDLC mandates type-safe design and review that can catch type-confusion flaws.

prevents

Application security requirements can specify strong typing and interface contracts that reduce type confusion.

prevents

Secure architecture principles promote type-safe languages and memory-safety mechanisms that mitigate type confusion.

References