CVE-2023-5344

Description

A heap-based buffer overflow vulnerability was found in Vim's trunc_string() function of the src/message.c file. This flaw allows an attacker to trick a user into opening a specially crafted file, triggering a heap-based buffer overflow that causes an application to crash, leading to a denial of service.

Statement

Red Hat Product Security has rated this issue as having a Low security impact, because the "victim" has to run an untrusted file IN SCRIPT MODE. Someone who is running untrusted files in script mode is equivalent to someone just taking a random python script and running it.

Since Red Hat Enterprise Linux 6, 7 are Out-of-Support-Scope for Low/Moderate flaws, the issue is not currently planned to be addressed in future updates for RHEL-6,7. Only Important and Critical severity flaws will be addressed at this time.

For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/ and Red Hat Enterprise Linux Life Cycle & Updates Policy: https://access.redhat.com/support/policy/updates/errata/.

Mitigation

Untrusted vim scripts with -s [scriptin] are not recommended to run.

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).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.37.5N/A
Attack VectorLocalNetworkN/A
Attack ComplexityLowLowN/A
Privileges RequiredNoneNoneN/A
User InteractionRequiredNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityLowNoneN/A
Integrity ImpactLowNoneN/A
Availability ImpactLowHighN/A

Vector

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

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

Red Hat CVSS v3 Score Explanation

PR:N: Because, no privileges required for attacker prior to attack as an attacker just have to pass malicious file to "vim" remotely or locally (Eg: via email or pen-drive and ask victim user just to open it in application), Hence, no privileges are needed, hence, PR:N

C:L, I:L:- because as per attack scenario, the victim user running vim with a malicious file (e.g. coming from an attacker) in -s [Script mode]. As such a crash does not pose any real security risk, unless it can be proven that the triggered issue can be used to send/modify valuable information to/by a remote/local attacker. So, most likely it will cause DoS, and crashing the application would not be a persistent denial of service, as an application should be relaunched and victim needs to reopen the malicious file again to re-crash. Hence, A:L.

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)

Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.

Integrity,Confidentiality,Availability,Access Control

Technical Impact: Execute Unauthorized Code or Commands; Bypass Protection Mechanism; Modify Memory

Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy. Besides important user data, heap-based overflows can be used to overwrite function pointers that may be living in memory, pointing it to the attacker's code. Even in applications that do not explicitly use function pointers, the run-time will usually leave many in memory. For example, object methods in C++ are generally implemented using function pointers. Even in C programs, there is often a global offset table used by the underlying runtime.

Integrity,Confidentiality,Availability,Access Control,Other

Technical Impact: Execute Unauthorized Code or Commands; Bypass Protection Mechanism; Other

When the consequence is arbitrary code execution, this can often be used to subvert any other security service.

Frequently Asked Questions

Want to get errata notifications? Sign up here.