CVE-2023-6546

Description

A race condition was found in the GSM 0710 tty multiplexor in the Linux kernel. This issue occurs when two threads execute the GSMIOC_SETCONF ioctl on the same tty file descriptor with the gsm line discipline enabled, and can lead to a use-after-free problem on a struct gsm_dlci while restarting the gsm mux. This could allow a local unprivileged user to escalate their privileges on the system.

Statement

This vulnerability is critical because it can be exploited to escalate privileges, directly threatening system security. Despite requiring local access and having a high attack complexity, the potential to severely impact confidentiality, integrity, and availability justifies its "Important" rating.

Mitigation

This flaw can be mitigated by preventing the affected `n_gsm` kernel module from being loaded. For instructions on how to blacklist a kernel module, please see https://access.redhat.com/solutions/41278.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score777
Attack VectorLocalLocalLocal
Attack ComplexityHighHighHigh
Privileges RequiredLowLowLow
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityHighHighHigh
Integrity ImpactHighHighHigh
Availability ImpactHighHighHigh

Vector

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

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

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

Understanding the Weakness (CWE)

Integrity,Other

Technical Impact: Alter Execution Logic; Unexpected State

The main problem is that -- if a lock is overcome -- data could be altered in a bad state.

Frequently Asked Questions

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