VulnerabilityPublished 2 Oct 2023Updated 3 Nov 2025

CVE-2023-5344: vim/vim · Heap-based Buffer Overflow

Affects vim/vimSource CVE Database V5

Not known to be exploited · CVSS 4.0 Medium : upgrade to 9.0.1969 when convenient.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.0 base score

4.0Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 1.2% chance of exploitation in 30 days – higher than 69% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 9.0.1969

CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Attack Vector: Local
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: Low

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 2 Oct 2023
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade vim/vim to 9.0.1969.

Affected software

Product	Affected	Fixed in
GitHubvim/vim`pkg:github/vim/vim`Other threats	Affected <9.0.1969	Fixed in 9.0.1969

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Monitor official vim repositories and security advisories for the release of patches addressing CVE-2023-5344 and apply updates promptly.
If you cannot patch yet, restrict local access to systems running vulnerable vim versions to trusted users only.
Employ application whitelisting and endpoint protection to detect abnormal vim crashes or suspicious local activity.
Incorporate vulnerability scanning tools that can detect outdated vim versions across organizational assets.
For critical systems, consider temporarily replacing vim with alternative text editors not affected by this vulnerability.
Educate system administrators and developers about the risk and encourage reporting of any unusual vim behavior.
Review and harden local user permissions to minimize the risk of exploitation by unauthorized users.
Implement robust logging and monitoring to quickly identify and respond to any denial of service incidents linked to vim crashes.

Description

Heap-based Buffer Overflow in GitHub repository vim/vim prior to 9.0.1969.

Impact

For European organizations, the primary impact of CVE-2023-5344 is potential denial of service due to application crashes or instability in vim. This could disrupt development environments, automated scripts, or system administration tasks that depend on vim, leading to productivity losses or operational delays. Since the vulnerability does not affect confidentiality or integrity, data breaches or unauthorized code execution are not immediate concerns. However, in environments where vim is integrated into critical automation or CI/CD pipelines, repeated crashes could cause cascading failures or delays. The requirement for local access limits remote exploitation risks, but insider threats or compromised internal accounts could leverage this vulnerability. Organizations with large developer teams or extensive use of vim on Linux/Unix servers should be particularly vigilant. The absence of known exploits reduces immediate risk but does not eliminate the need for proactive mitigation.

CWE-122Heap-based Buffer Overflow (opens in a new tab)
Variant weaknessLikelihood of exploit: HighCWE Top 25 (2025): #16
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
Pre-design: Use a language or compiler that performs automatic bounds checking.
Architecture and Design
Use an abstraction library to abstract away risky APIs. Not a complete solution.
Operation · Build and Compilation · Environment Hardening
Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index…
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
Attack patterns
Forced Integer Overflow (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 3 Nov 2025, 22:09 UTC

WeaknessesCWE-122

Technical details

References

Community reviews

Related threats