VulnerabilityPublished 11 May 2026

CVE-2026-43656: Apple iOS and iPadOS · Out-of-bounds Write

Affects Apple iOS and iPadOSSource CVE Database V5

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Not known to be exploited · CVSS 7.3 High : upgrade to 26.5 or 18.7.9 soon.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

7.3High

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 18% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 26.5, 18.7.9, 15.7.7 +1

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

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

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

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
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: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on 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 11 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 30 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.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), 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 iOS and iPadOS to 26.5 or 18.7.9; macOS to 26.5, 15.7.7 or 14.8.7.

Affected software

Product	Affected	Fixed in
AppleiOS and iPadOS	Affected <26.5	Fixed in 26.5
AppleiOS and iPadOS	Affected <18.7.9	Fixed in 18.7.9
ApplemacOS	Affected <26.5	Fixed in 26.5
ApplemacOS	Affected <15.7.7	Fixed in 15.7.7
ApplemacOS	Affected <14.8.7	Fixed in 14.8.7

AI-suggested

Apple has released fixes in iOS 18.7.9, iPadOS 18.7.9, and corresponding macOS versions that address this vulnerability through improved input validation. Users and administrators should apply these updates promptly once confirmed available. Patch status is not explicitly confirmed in the provided data; therefore, verify the current remediation status with official Apple security advisories before taking action.

Description

CVE-2026-43656 is a high-severity vulnerability in Apple iOS and iPadOS where parsing a maliciously crafted file may cause an unexpected app termination due to an out-of-bounds write issue. Apple addressed this vulnerability with improved input validation in iOS 18.7.9, iPadOS 18.7.9, and corresponding macOS versions. The vulnerability has a CVSS score of 7.3, indicating significant impact on confidentiality, integrity, and availability. No known exploits are reported in the wild. Patch status is not explicitly confirmed in the provided data, so users should verify with official Apple advisories for remediation guidance.

Impact

Successful exploitation may cause unexpected termination of applications processing maliciously crafted files, leading to denial of service and partial loss of confidentiality and integrity. The vulnerability affects Apple iOS and iPadOS platforms and could disrupt normal app operations. There are no known exploits in the wild at this time.

Summary

This vulnerability involves an out-of-bounds write (CWE-787) triggered by parsing a maliciously crafted file on Apple iOS and iPadOS devices. The issue can lead to unexpected application termination, potentially impacting system stability and availability. Apple has fixed the issue by improving input validation in iOS 18.7.9, iPadOS 18.7.9, and related macOS releases. The CVSS 3.1 base score is 7.3 (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L), reflecting network attack vector, low attack complexity, no privileges or user interaction required, and partial impact on confidentiality, integrity, and availability. No vendor advisory or patch links are provided in the input, so patch availability is not explicitly confirmed here.

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

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 19 May 2026, 10:53 UTC

WeaknessesCWE-787

Technical details

References

Community reviews

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