GHSA-v446-xwfm-x7mr · 深刻度： high — Issue summary: When an application drives an AES-OCB context through the public EVP_Cipher() one...
Issue summary: When an application drives an AES-OCB context through the public EVP_Cipher() one-shot interface, the application-supplied initialisation vector (IV) is silently discarded. Impact summary: Every message encrypted under the same key uses the same effective nonce regardless of the IV supplied by the caller, resulting in (key, nonce) reuse and loss of confidentiality. If the same code path is used to compute the authentication tag, the tag depends only on the (key, IV) pair and not on the plaintext or ciphertext, allowing universal forgery of arbitrary ciphertext from a single captured message. OpenSSL provides two ways to drive a cipher: the documented streaming interface (EVP_CipherUpdate / EVP_CipherFinal_ex) and a lower-level one-shot, EVP_Cipher(), whose documentation explicitly recommends against use by applications in favour of EVP_CipherUpdate() and EVP_CipherFinal_ex(). The OCB provider's streaming handler flushes the application-supplied IV into the OCB context before processing data; the one-shot handler did not. Every call to EVP_Cipher() on an AES-OCB context therefore ran with the all-zero key-derived offset state left by cipher initialisation, regardless of the caller's IV. If EVP_EncryptFinal_ex() is subsequently used to obtain the authentication tag, the deferred IV setup runs at that point and clears the running checksum that should have been accumulated over the plaintext. The resulting tag is a function of (key, IV) only and verifies against any ciphertext produced under the same (key, IV) pair. The OpenSSL SSL/TLS implementation is not affected: AES-OCB is not a TLS cipher suite, and libssl does not call EVP_Cipher() in any case. Applications that drive AES-OCB through the documented streaming AEAD API (EVP_CipherUpdate / EVP_CipherFinal_ex) are not affected. Only applications that combine the AES-OCB cipher with the EVP_Cipher() one-shot API are vulnerable. The FIPS modules in 4.0, 3.6, 3.5, 3.4 and 3.0 are not affected by this issue, as AES-OCB is outside the OpenSSL FIPS module boundary.
総合評価: CVE-2026-45445 は低リスク（38.8/100）。CVSS 深刻度は高。悪用される可能性が高い（EPSS 0.33%、24 パーセンタイル） 推奨対応: 悪用情報と EPSS の推移を監視し、必要に応じて優先度を見直してください。
リスクは変動します。再評価に基づき、本ページの表示内容を更新しています。
EPSS は日次で悪用されやすさの相対度合いを推定します。パーセンタイルは採点済み CVE の中での相対位置（高いほど相対的に深刻）を示します。
| # | 日付 | 旧 EPSS スコア | 新 EPSS スコア | Δ（新 − 旧） |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.02% | 0.33% | +0.31% |
| 2 | 2026-06-10 | — | 0.02% | — |
EPSS の全履歴 （全 2 件）
この CVE の CVSS 指標。
| ベーススコア | バージョン | 深刻度 | ベクトル | 悪用しやすさ | 影響 | スコアの出典 |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
GHSA-v446-xwfm-x7mr · 深刻度： high — Issue summary: When an application drives an AES-OCB context through the public EVP_Cipher() one...
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
unimportant | CVE-2026-45445 unimportant priority: Debian including 1 source packages (openssl), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2026-45445 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2026-45445 |
suse
|
medium | CVE-2026-45445 severity moderate: SUSE including 55 source package names (compat-openssl098, latest:libexpat1-2.7.1-4.1, …), 361 product×package rows across 70 product lines (Container suse/sl-micro/6.0/baremetal-os-container, Container suse/sl-micro/6.0/base-os-container, … (70 product lines)): Known Not Affected 236, Fixed 69, First Fixed 56. | https://www.suse.com/security/cve/CVE-2026-45445/ |
ubuntu
|
medium | CVE-2026-45445 medium priority: Ubuntu including 5 source packages (edk2, nodejs, openssl, openssl-fips, openssl1.0), 35 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): not-affected 14, DNE 8, needs-triage 8, released 4, needed 1. | https://ubuntu.com/security/CVE-2026-45445 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| openssl | openssl | >= 3.0.0, < 3.0.21 | cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* |
| openssl | openssl | >= 3.4.0, < 3.4.6 | cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* |
| openssl | openssl | >= 3.5.0, < 3.5.7 | cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* |
| openssl | openssl | >= 3.6.0, < 3.6.3 | cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* |
| openssl | openssl | 4.0.0 | cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:* |