CVE-2026-42327

rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.9.7 to before 0.10.79, X509Ref::ocsp_responders returns OCSP responder URLs from a certificate's AIA extension as OpensslString, whose Deref<Target = str> wraps the raw bytes with str::from_utf8_unchecked. OpenSSL does not enforce that the underlying IA5String is ASCII, so a certificate with non-UTF-8 bytes in its OCSP accessLocation causes safe Rust code to construct a &str that violates the UTF-8 invariant — resulting in undefined behavior. This vulnerability is fixed in 0.10.79.

CVSS

No CVSS.

References

Link	Resource
https://github.com/rust-openssl/rust-openssl/security/advisories/GHSA-xp3w-r5p5-63rr

Configurations

No configuration.

History

14 May 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-14 21:16

Updated : 2026-05-15 14:55

NVD link : CVE-2026-42327

Mitre link : CVE-2026-42327

CVE.ORG link : CVE-2026-42327

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

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