High
rust-openssl — security advisory
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 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.
- Products
- rust-openssl
- Affected versions
- 0.10.23-1, 0.10.23-1ubuntu0.1~esm1, 0.10.29-1, 0.10.36-1, 0.10.36-1ubuntu0.1~esm1, 0.10.45-1, 0.10.57-1, 0.10.57-1ubuntu0.1~esm1, 0.10.70-1, 0.10.72-1, 0.10.73-1, 0.10.81-1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-42327
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:03 UTC · Revision 1
Source evidence
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 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.
osv:UBUNTU-CVE-2026-42327
rust-openssl
Fixed versions: Not specified
rust-openssl
Fixed versions: Not specified
rust-openssl
Fixed versions: Not specified
rust-openssl
Fixed versions: Not specified
rust-openssl
Fixed versions: Not specified
rust-openssl
Fixed versions: Not specified
Complete source record
{
"id": "9481fb1d7f3a7db14a50e4b2f4064df8ed7f6c0c76e2cf113b59107d2c9b8048",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-42327",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-42327",
"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 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.",
"evidence": "osv:UBUNTU-CVE-2026-42327",
"products": [
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],
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"structured": {
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"aliases": [
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],
"metrics": [
{
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},
{
"type": "Ubuntu",
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"affected": [
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"package": {
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},
"versions": [
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"database_specific": {
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},
"ecosystem_specific": {
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},
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"0.10.57-1",
"0.10.57-1ubuntu0.1~esm1"
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},
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}
],
"modified": "2026-10-17T13:00:05.436581379Z",
"provider": "osv",
"upstream": [
"CVE-2026-42327"
],
"references": [
"https://ubuntu.com/security/CVE-2026-42327",
"https://www.cve.org/CVERecord?id=CVE-2026-42327",
"https://github.com/rust-openssl/rust-openssl/security/advisories/GHSA-xp3w-r5p5-63rr"
]
},
"related_cves": [
{
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"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 360305,
"published_at": "2026-05-14T21:16:00+00:00"
}