Description
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.
Affected products
apple: swiftnio ssl
References2
- github.com/apple/swift-nio-ssl/security/advisories/GHSA-xfxg-99… Vendor AdvisoryExploit
- github.com/apple/swift-nio-ssl/security/advisories/GHSA-xfxg-99… Vendor AdvisoryExploit
Metrics
- CVSS 3.1
-
7.7
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 0% percentile: 1 · as of 14 November 2026
- CWE
- CWE-125
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