OpenSSLに制限のないリソース割り当ての脆弱性（CVE-2026-35189）
概要
OpenSSLに制限のないリソース割り当ての脆弱性が確認されました。
バージョン 1.0.2 以上 1.0.2zs 未満、1.1.1 以上 1.1.1zj 未満、3.0.0 以上 3.0.23 未満、3.4.0 以上 3.4.8 未満、3.5.0 以上 3.5.9 未満、3.6.0 以上 3.6.5 未満 ほか1範囲に影響があります。
修正版 1.0.2zs / 1.1.1zj / 3.0.23 / 3.4.8 / 3.5.9 / 3.6.5 / 4.0.3 への更新が推奨されます。
脆弱性の基本情報
| 脆弱性ID | CVE-2026-35189 |
|---|---|
| 脆弱性の種類 | 制限のないリソース割り当て |
| 危険度 | 中 |
| CVSSスコア |
5.3（CVSS v3.1） CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| 公開日 | 2026年9月29日 |
| 更新日 | 2026年10月8日 |
影響を受ける製品
| 製品 | 影響を受けるバージョン | 修正版 | 出典 |
|---|---|---|---|
| OpenSSL |
1.0.2 以上 1.0.2zs 未満、1.1.1 以上 1.1.1zj 未満、3.0.0 以上 3.0.23 未満、3.4.0 以上 3.4.8 未満、3.5.0 以上 3.5.9 未満、3.6.0 以上 3.6.5 未満 ほか1範囲 | 1.0.2zs / 1.1.1zj / 3.0.23 / 3.4.8 / 3.5.9 / 3.6.5 / 4.0.3 | NVD（National Vulnerability Database / NIST） |
推奨対応
- OpenSSLを、ご利用中の系列に対応する修正版（1.0.2zs / 1.1.1zj / 3.0.23 / 3.4.8 / 3.5.9 / 3.6.5 / 4.0.3）またはそれ以降の公式最新版へ更新してください。
- OpenSSLを OS・ディストリビューションのパッケージで利用している場合は、提供元の公式セキュリティ更新が適用されているかを確認してください（独自に修正が取り込まれている場合があります）。
情報元の原文
NVD（National Vulnerability Database / NIST）
Issue summary: A certificate with many nameRelativeToCRLIssuer CRL
distribution points causes disproportionate heap growth when OpenSSL caches
X.509 extensions.
Impact summary: Receiving a crafted certificate from a malicious peer can lead
to significant memory pressure and possible Denial of Service in clients or
in servers that solicit client certificates.
CWE: CWE-770: Allocation of Resources Without Limits or Throttling
Description: A certificate or a set of certificates that fits under the limit for
size of certificates accepted from the peer (~100 KiB) can result in allocation
of several hundred MiB of resident memory on the receiving side
during a normal TLS handshake. This may be enough to crash the client or
server, if multiple concurrent connections lead to similarly large memory
allocations.
The fix postpones processing of the CRL distribution points extensions in
certificates to the time when the processed value is required for CRL processing.
This avoids keeping large memory allocations for a long time when such
certificates are received.
FIPS impact: no
The affected code is outside the FIPS module boundary.
利用条件：米国政府の著作物（パブリックドメイン）・原文のまま掲載
Copyright 1999-2026 The MITRE Corporation
CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.
CVE List（CVE Program）
Excessive Memory Allocation in Relative CRLDP Processing
Issue summary: A certificate with many nameRelativeToCRLIssuer CRL
distribution points causes disproportionate heap growth when OpenSSL caches
X.509 extensions.
Impact summary: Receiving a crafted certificate from a malicious peer can lead
to significant memory pressure and possible Denial of Service in clients or
in servers that solicit client certificates.
CWE: CWE-770: Allocation of Resources Without Limits or Throttling
Description: A certificate or a set of certificates that fits under the limit for
size of certificates accepted from the peer (~100 KiB) can result in allocation
of several hundred MiB of resident memory on the receiving side
during a normal TLS handshake. This may be enough to crash the client or
server, if multiple concurrent connections lead to similarly large memory
allocations.
The fix postpones processing of the CRL distribution points extensions in
certificates to the time when the processed value is required for CRL processing.
This avoids keeping large memory allocations for a long time when such
certificates are received.
FIPS impact: no
The affected code is outside the FIPS module boundary.
利用条件：CVE の利用条件（CVE Terms of Use）・原文のまま掲載
Copyright 1999-2026 The MITRE Corporation
CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.
情報元
- NVD（National Vulnerability Database / NIST）
https://nvd.nist.gov/vuln/detail/CVE-2026-35189 - CVE List（CVE Program）
https://www.cve.org/CVERecord?id=CVE-2026-35189