7.7highHigh
CVE-2026-43820
Apple Swiftnio Ssl
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.
Exploitation status
- Published references include exploit or proof-of-concept material. There is no confirmation it is being used in real attacks.
- A vendor advisory or patch reference has been published.
What the metrics mean
- It is requires local access to the machine.
- For an attacker who can reach it, no special conditions are needed to exploit it.
- To exploit it, no account is needed.
- Beyond that, no action by a user is required.
Scoring
- CVSS
- 7.7 (v3.1)
- Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H- Weakness
- CWE-125
- Assigned by
- product-security@apple.com
Dates
- Published
- 2026-07-23
- Last modified
- 2026-09-04
- Sources
- NVD
Affected products
- Apple Swiftnio Ssl2.18.0 - 2.37.2
As listed in the NVD configuration data. Not a statement about your estate.