CVE-2026-43820

NIOSSLCertificate._subjectAlternativeNames provides access to the raw bytes for a cert's SANs. NIOSSL provides access to a buffer assumed to be backed by an ASN1_STRING, but not all SANs are backed by ASN1_STRING, so accessing the buffer for such a type can lead to out-of-bounds memory access. This vulnerability is addressed in swift-nio-ssl version 2.37.2.

CVSS v3 7.7 HIGH

7.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.5 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/apple/swift-nio-ssl/security/advisories/GHSA-xfxg-9975-pc2j	Vendor Advisory Exploit
https://github.com/apple/swift-nio-ssl/security/advisories/GHSA-xfxg-9975-pc2j	Vendor Advisory Exploit

Configurations

Configuration 1 (hide)

cpe:2.3:a:apple:swiftnio_ssl:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-23 15:17

Updated : 2026-09-04 18:21

NVD link : CVE-2026-43820

Mitre link : CVE-2026-43820

CVE.ORG link : CVE-2026-43820

JSON object : View

Products Affected

apple

swiftnio_ssl

CWE

CWE-125

Out-of-bounds Read

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