CVE-2025-43353VulnerabilityPublished 15 Sep 2025Updated 2 Apr 2026

CVE-2025-43353: Apple macOS · Processing a maliciously crafted string may lead to heap corruption

Affects Apple macOSSource CVE Database V5

Not known to be exploited · CVSS 5.5 Medium · fixed in 15.7 : update Apple macOS when convenient.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

5.5Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 15.7

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

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

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: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
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: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 15 Sep 2025
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 2026-10-26.

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 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

Affected software

Product	Affected	Fixed in
Apple macOS	Affected =0	Fixed in–

AI-suggested

1. Apply the latest macOS updates immediately, specifically versions Sequoia 15.7, Sonoma 14.8, and Tahoe 26 or later, which contain the fix for this vulnerability. 2. Restrict local user access to trusted individuals and enforce least privilege principles to minimize the risk of exploitation by untrusted users. 3. Educate users to avoid processing untrusted or suspicious strings, especially from unknown sources or unsolicited communications. 4. Implement application whitelisting and sandboxing to limit the impact of potential heap corruption in user-level applications. 5. Monitor system logs and crash reports for signs of heap corruption or abnormal application behavior that could indicate attempted exploitation. 6. Use endpoint detection and response (EDR) tools capable of detecting memory corruption anomalies. 7. For high-security environments, consider disabling or restricting features that process external strings if feasible until patches are applied. 8. Maintain regular backups and incident response plans to recover quickly from potential denial-of-service events caused by exploitation.

Description

The issue was addressed with improved bounds checks. This issue is fixed in macOS Sequoia 15.7, macOS Sonoma 14.8, macOS Tahoe 26. Processing a maliciously crafted string may lead to heap corruption.

Impact

The primary impact of CVE-2025-43353 is on system availability. Heap corruption can cause applications or the entire operating system to crash, leading to denial-of-service conditions. While the vulnerability does not directly compromise confidentiality or integrity, repeated exploitation or chaining with other vulnerabilities could increase risk. Organizations relying on macOS for critical operations may experience service interruptions or degraded performance. The requirement for local access and user interaction limits large-scale remote exploitation but insider threats or social engineering attacks could still exploit this flaw. Environments with shared macOS systems, such as enterprise networks, educational institutions, or public access computers, are particularly vulnerable. The absence of known exploits in the wild currently reduces immediate risk but does not preclude future exploitation. Failure to patch could expose organizations to operational disruptions and potential targeted attacks leveraging this vulnerability.

CWE-787Out-of-bounds Write (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #5
The product writes data past the end, or before the beginning, of the intended buffer.
Requirements · Language Selection
Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
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)
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 Apr 2026, 02:04 UTC

WeaknessesCWE-787

Technical details

References

Community reviews

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