CVE-2026-42327 (GCVE-0-2026-42327)
Vulnerability from cvelistv5 – Published: 2026-05-14 20:17 – Updated: 2026-05-15 18:05
VLAI
EPSS
VEX
Title
rust-openssl: undefined behavior in X509Ref::ocsp_responders for certificates with non-UTF-8 OCSP URLs
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-15 16:28 UTC
CWE
- CWE-20 - Improper Input Validation
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/rust-openssl/rust-openssl/secu… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| rust-openssl | rust-openssl |
Affected:
>= 0.9.7, < 0.10.79
|
guessed |
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| Author | Source | Type | Date | Other |
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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