What is CVE-2026-43823?

CVE-2026-43823 is a high-severity vulnerability in Apple Swift-Crypto, classified under Double Free. CVSS score: 7.5/10. Published 2026-07-23.

How severe is CVE-2026-43823?

High severity. CVSS v3 base score is 7.5 out of 10.

Double Free in Apple Swift-Crypto

CVE-2026-43823

When initializing an RSA public key from DER or PEM bytes throws an error, the EVP_PKEY* is double-freed: first in the catch block, then in the deinit. This can lead to a crash on future memory allocations. This double-free manifests when BoringSSL cannot decode the public key from the bytes provided. This vulnerability is addressed in swift-crypto version 4.5.1.

Vulnerability class: Double Free

EPSS: 0.003 (17.0th percentile) — read the EPSS interpretation.

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.

Affected products

Apple Swift-crypto — versions 0

Weakness classification (CWE)

CWE-415 — Double Free

References

product-security@apple.com (Vendor Advisory)

Frequently asked questions

What is CVE-2026-43823?: CVE-2026-43823 is a high-severity vulnerability in Apple Swift-Crypto, classified under Double Free. CVSS score: 7.5/10. Published 2026-07-23.
How severe is CVE-2026-43823?: High severity. CVSS v3 base score is 7.5 out of 10.