CVE-2026-43823Public exploitNetwork attack vector

Application crash via malformed RSA public key

Published Jul 23, 2026 · Updated Jul 23, 2026

Double-free in CryptoExtras RSA parsing in Apple Swift Crypto 3.2.0 through 4.5.0 allows remote attackers to crash applications. The BoringSSLRSAPublicKey DER and PEM initializers free their EVP_PKEY pointer after decoding fails, and deinitialization releases the same pointer again. Reachability requires an application to pass an untrusted malformed key to an affected _RSA encryption, signing, or blind-signing public-key initializer; the reported consequence is a later allocation crash.

CVSS severity7.5
High
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Double-free in CryptoExtras RSA parsing in Apple Swift Crypto 3.2.0 through 4.5.0 allows remote attackers to crash applications. The BoringSSLRSAPublicKey DER and PEM initializers free their EVP_PKEY pointer after decoding fails, and deinitialization releases the same pointer again. Reachability requires an application to pass an untrusted malformed key to an affected _RSA encryption, signing, or blind-signing public-key initializer; the reported consequence is a later allocation crash.

The record

CVE
CVE-2026-43823
Published
Jul 23, 2026
Updated
Jul 23, 2026
Vendor
Apple
Product
Swift Crypto
Classifications
CWE-415, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 23, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <4.5.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Apple · Swift Cryptoversion=0 <4.5.1

Published CVSS scores

7.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-415Double Free
T1499Endpoint Denial of Service

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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