CVE-2025-0343 — HIGH (7.5) — White Hats Nepal

Vulnerability Description

Swift ASN.1 can be caused to crash when parsing certain BER/DER constructions. This crash is caused by a confusion in the ASN.1 library itself which assumes that certain objects can only be provided in either constructed or primitive forms, and will trigger a preconditionFailure if that constraint isn't met. Importantly, these constraints are actually required to be true in DER, but that correctness wasn't enforced on the early node parser side so it was incorrect to rely on it later on in decoding, which is what the library did. These crashes can be triggered when parsing any DER/BER format object. There is no memory-safety issue here: the crash is a graceful one from the Swift runtime. The impact of this is that it can be used as a denial-of-service vector when parsing BER/DER data from unknown sources, e.g. when parsing TLS certificates.

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

NONE

Availability

HIGH

Related Weaknesses (CWE)

CWE-228

References

https://github.com/apple/swift-asn1/security/advisories/GHSA-w8xv-rwgf-4fwh

FAQ

What is CVE-2025-0343?

CVE-2025-0343 is a vulnerability with a CVSS score of 7.5 (HIGH). Swift ASN.1 can be caused to crash when parsing certain BER/DER constructions. This crash is caused by a confusion in the ASN.1 library itself which assumes that certain objects can only be provided i...

How severe is CVE-2025-0343?

CVE-2025-0343 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2025-0343?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.