CVE-2026-43823: apple swift-crypto Double Free
Vulnerability summary
CVE-2026-43823 is a high (CVSS 7.5) Double Free vulnerability in apple swift-crypto. EPSS estimates a 0.43% chance of exploitation in the next 30 days, higher than 37.1% of scored vulnerabilities.
Severe, CVSS 7.5 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 0% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 2Timeline
- 23-07-2026PublishedVulnerability first disclosed.
- 23-07-2026Last modifiedVulnerability information updated.
Description
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.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.43%
Chance of exploitation in the next 30 days
Percentile
37%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.43% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Apple1 product
- swift-crypto< 4.5.1 | ≥ 3.2.0, ≤ 4.5.1
1 vendor · 1 product