Vulnerability in openssl (CVE-2026-42327)
Summary
Vulnerability in openssl (CVE-2026-42327). Risk of unauthorized operations or information disclosure. Exploitable via OpensslString. Mitigation: upgrade to 0.10.79 or later.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-42327 has been found in openssl.
Attackers can target a specific entry point like OpensslString over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade openssl to 0.10.79 or later.
If unsure, ask your IT team or search "openssl CVE-2026-42327" on the vendor's site.
CVE-2026-42327 (openssl) — CWE-20
Attack surface: OpensslString
Patched: 0.10.79 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-20) exists in openssl. Attackers reach the vulnerable code path via OpensslString.
Check the vendor advisory for the affected versions of openssl. Attack surface: OpensslString.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 0.10.79.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'openssl' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'openssl' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
opensslを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade openssl to 0.10.79ステージング環境で 0.10.79 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-42327 rust-openssl
- Ubuntu UBUNTU-CVE-2026-42327 rust-openssl
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com