Out-of-bounds Read in Apple macOS
CVE-2026-28815
A remote attacker can supply a short X-Wing HPKE encapsulated key and trigger an out-of-bounds read in the C decapsulation path, potentially causing a crash or memory disclosure depending on runtime protections. This issue is fixed in swift-crypto version 4.3.1.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (44.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 44.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Apple macOS — versions 4.0.0
- Apple Swift-Crypto
Weakness classification (CWE)
References
- github.com/apple/swift-crypto/security/advisories/GHSA-9m44-rr2w-ppp7 (Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-28815?
- CVE-2026-28815 is a high-severity vulnerability in Apple macOS, classified under Out-of-bounds Read. CVSS score: 7.5/10. Published 2026-04-03.
- How severe is CVE-2026-28815?
- High severity. CVSS v3 base score is 7.5 out of 10.